1. Chemistry

How many grams of dry NH4Cl need to be added to 2.10L of a 0.600M solution of ammonia,NH3 , to prepare a buffer solution that has a pH of 9.00? Kb for ammonia is 1.8x10^-5. I just wanted to make sure I dd this write, can you please check my work? Thank

2. Physics

Let vector B = 8.8 m, 75 degrees counterclockwise from the vertical. a) Find the x- and y-components of vector B in the normal coordinate system (where x is a horizontal line and y is a vertical line...both intersect each other). b) Find the x- and

3. Physics

a 2.5kg block initially at rest on horizontal surface. A horizontal force F of magnitude 6N and a vertical force P are the applied to the block. The coefficients of friction for the block and surface are Ms=0.4 and Mk=0.25.Determine the magnitude of the

4. Calculus

If a rock is thrown upward on the planet Mars with a velocity of 14 m/s, its height in meters t seconds later is given by y = 14t − 1.86t^2. Estimate the instantaneous velocity when t = 1.

5. chemistry

consider the reaction, 2Al(OH)3+3H2SO4---->Al2(SO4)3+6H2O a. Given that 152g of H2SO4 reacts with 234g of Al(OH)3 Howmany grams of Al2(SO4)3 will be theoretical generated? b. which of the reactants is the limiting reagent? c. If the actuall yield was 135 g

6. College Physics

Electronics and inhabitants of the International Space Station generate a significant amount of thermal energy that the station must get rid of. The only way that the station can exhaust thermal energy is by radiation, which it does using thin, 2.2

7. Calculus

If a rock is thrown upward on the planet Mars with a velocity of 7 m/s, its height in meters t seconds later is given by y = 7t − 1.86t2. (Round your answers to two decimal places.) (a) Find the average velocity over the given time intervals. (i) [1, 2]

8. Physics

A 2 kg ball of putty moving to the right at 3m/s has a head-on inelastic collision with a 1 kg ball of putty moving to the left at 3m/s. What is the final magnitude and direction of the velocity of the stuck together balls after the collision?

9. Algebra

Jake scored x points in the first basketball game. He scored 2 fewer points in the next game. His teammate, Jack, scored 2y points in the first game and 4 more than twice as many points in the next game. Write and simplify an expression for the total

10. NEWTON'S LAWS (FORCES)

Two boxes, A and B, are connected to each end of a light vertical rope, as shown in the following figure. A constant upward force 78.0N is applied to box A . Starting from rest, box B descends 12.3 m in 3.80s . The tension in the rope connecting the two

11. physics

Two boxes, A and B, are connected to each end of a light vertical rope, as shown in the following figure. A constant upward force 78.0N is applied to box A . Starting from rest, box B descends 12.3 m in 3.80s . The tension in the rope connecting the two

12. physics

A quaterback throws the football to a stationary receiver who is 31.5m down the field. If the football is thrown at an initial angle of 40.0 degrees to the ground, at what initial speed must the quaterback throw the ball for it to reach the receiver? What

13. Chemistry

Assuming the sample is pure sodium sulfate, how many mL of 5% BaCl2.2H20 solution would be required to precipitate the sulfate. Density of barium shloride solution of 1.00 g/mL.

14. Calculus

f a rock is thrown upward on the planet Mars with a velocity of 7 m/s, its height in meters t seconds later is given by y = 7t − 1.86t^2. (Round your answers to two decimal places.) Estimate the instantaneous velocity when t = 1.

15. calculus

The given curve is rotated about the y-axis. Find the area of the resulting surface. y = 1/4x^2 − 1/2ln x, 4 ≤ x ≤ 5 The answer is supposed to be 64/3*pi

16. geometry

A table is set for dinner. Can the legs of the table and the top of the table lie in parallel planes? Why or why not?

17. maths

A broken clover has 2 leaves, a normal clover has 3 leaves and a lucky clover has 4 leaves. In a bunch of these clovers , there are twice as many normal clovers as broken clovers and 5 times as many normal clovers as lucky clovers. The bunch has a total of

18. Physical Science

A certain metal surface emits electrons when light is shone on it. (a)How can the number of electrons per second be increased? (b) How can the energies of the electrons be increased?

19. Chem

The field of nanotechnology offers some intriguing possibilities, such as the creation of fibers one atom wide. Suppose you were able to string together 1.00 mol Ag atoms, each of radius 144 pm, into one of these fibers by encapsulating them in carbon

20. math

what is the value of the 8 in 387?

21. Calculus

Find the constant c so that lim [x^2 + x + c]/[x^2 - 5x + 6] exists. x->3 For that value of c, determine the limit. (Hint: Find the value of c for which x - 3 is a factor of the numerator.)

22. College Chemistry

Plaster of Paris is the compound calcium sulfate hemihydrate, CaSO4*1/2H2O What mass of water is liberated when a 2.763 gram sample is heated to constant mass? The sample is 2.763 grams How much of the 2.763 gram sample is water? I need an amount in grams.

23. precal

A contractor needs to know the height of a building to estimate the cost of a job. From a point 84 feet away from the base of the building, the angle of elevation to the top of the building is found to be 44 degrees and 23'. Find the height of the

24. Chemistry

If performing a gravimetric sulfate experiment and you use ordinary filter paper instead of ashless filter paper, would results be too high or too low? If I'm trying to calculate percentage of sulfate in a sample and I used ordinary filter paper, the paper

25. Physics

A)Two point charges, +3.90 ìC and -7.50 ìC, are separated by 3.30 m. What is the electric potential midway between them? B)The drawing shows four point charges. The value of q is 1.3 ìC, and the distance d is 0.95 m. Find the total potential at the

26. Linear equations

Please help me solve this problem- Find an equation for the line perpendicular to 6x+2y=-2 having the same y-intercept as -4x-3y=6

27. physics

this is my last one i couldn't find the answer please help ??? Two workers pull horizontally on a heavy box, but one pulls twice as hard as the other. The larger pull is directed at 25.0 o west of north, and the resultant of these two pulls is 400.0 N

28. statistics

Suppose that contamination particle size in micrometers can be modeled as f(x) = 2x−3 for 1 < x. a. Show that f(x) is a probability density function. b. Find the mean X.

29. math

How many dollars is 200 quarters, 150 dimes, and 300 pennies

30. Statistics-confused

A candidate for a political office claims that he will win the election. A poll is conducted, and 35 of 150 voters indicate that they will vote for the candidate, 100 voters indicate that they will vote for his opponent, and 15 voters are undecided. a.

31. physics

A 62.0-kg runner has a speed of 4.90 m/s at one instant during a long-distance event.

32. College Chemistry

Plaster of Paris is the compound calcium sulfate hemihydrate, CaSO4*1/2H2O What mass of water is liberated when a 2.763 gram sample is heated to constant mass?

33. Chem

Calculate the amount (in moles) of H₂O in 2.00g of Na₂CO₃ ⋅ 10H₂O. Thanks so much!!

34. Finance

3) Which of the following statements is true concerning home equity loans? A. Home equity loans are generally installment loans with a 5-15 year term. B. Home equity loan interest is never tax-deductible. C. Home equity loans are secured by all of the

35. Economics

The schedule below shows the level of output that can be produced using different levels of input. A unit of input costs \$80 and the fixed costs of running your business are \$50. Input Output 0 0 1 2 2 6 3 9 4 11 5 12 1. What is your AVC of producing 11

36. english

He suffered an injury to his knee, and this is causing him pain and discomfort. Help find the verbs

37. College Physics

In this problem you will estimate the heat lost by a typical house, assuming that the temperature inside is T(in) = 20 degrees celcius and the temperature outside is T(out) = 0 degrees celcius. The walls have fiberglass insulation, which dominates the heat

38. physics

A particle moving with uniform acceleration in a straight line was first observed to be moving at 4.5 m/s. After 10 sec, it was moving at 6.8 m/s. What is its acceleration?

39. Pre-Calc

Could someone show me how to solve these two problems-I have 10 of each kind to do this weekend and I'm really lost 1. Find product of 8(cos pi/2 + i sin pi/2) * 1/2(cos pi/6 + i sin pi/6) 2. Same problem but find quotient instead of product Please someone

40. P Science

If Planck's constant were smaller than it is, would quantum phenomena be more or less conspicuous than they are now?

41. Chem

Calculate the amount (in moles) of Cu²+ ions in 3.00g of CuBr₂. Thank you so much for the help!!

42. algebra

write an expression that has five terms and simplifies to 5m3 + 4n. Please give me the steps

43. Statistics

Describe whether the following study would most likely be “observational” or “experimental”, and why it would be so. * Mystery shoppers monitor the preferences at a shopping mall

44. physics 12

An 884 kg satellite in orbit around a planet has a gravitational potential energy of -5.44*10^10 J. The orbital radius of the satellite is 8.52*10^6 m and its speed is 7.84*10^3 m/s. A) What is the mass of the planet? B) What is the kinetic energy of the

45. algebra

the function W(d)=0.112d approximates the amount in centimeters of water that results from d cm of snow melting. Find the amount of water that results from snow melting from depths of 18 cm, 49 cm, and 98 cm. I am having problems figuring this out and I

46. Physics

A 0.45kg shuffleboard puck is given an initial velocity down the playing surface of 4.5 m/s. If the coefficient of friction between the puck and the surface is 0.20, how far will the puck slide before coming to rest?

47. physics 12

A spacecraft of mass 470 kg rests on the surface of an asteroid of radius 1400 m and mass 2.0*10^12. How much energy must be expended so that the spacecraft may rise to a height of 2800 m above the surface of the asteroid? Thanks.

48. Statistics-confused

A candidate for a political office claims that he will win the election. A poll is conducted, and 35 of 150 voters indicate that they will vote for the candidate, 100 voters indicate that they will vote for his opponent, and 15 voters are undecided. a.

49. Chemistry

I am really stuck, I have tried to look these up everywhere and I keep getting different answers. I have to find the balanced equations for: Magnesium + Citric acid Zinc + citric acid Copper + Citric acid Manganese + Citric acid If I can have some help it

50. CIS 115

I need help with the visual logic flowchart for the following problem: A local deli sells lunch value meals that consist of a sandwich, soup and a drink. The price of each meal depends on the actual items ordered. Write a program that asks the cashier to

51. english

suki and lee wake up earl this morning . They want to go to grandma's house in the city.first they put on their clothes,then they ate their breakfast.they will ride with their parents in the car to grandma's house.they will take for her some food to eat.

52. mathematics

1. 3/(x+2)+4/(x-5)=2/3 2. 5/(3x+8)=4/(3x-8)

53. Microeconomics

Baseballs cost \$5 and baseball gloves cost \$20. Assume you have \$100 total to spend on these items. Construct a table similar to the one on page 158. What is the point, based on the Equimarginal Rule, that has equal marginal benefit (or the closest) for

54. accounting

On January 2, 2007, a company issued \$100,000 of 5%, 10 year bonds. The bonds will mature in ten years. The bonds were sold for for 95% (or .95 of par) and will pay interest semi-annually, or twice a year, on June 30 and Dec 31. Record the journal entries

55. physics

You are given a vector in the plane that has a magnitude of 86.0 units and a component of -30.0 units. What are the two possibilities for its component?

56. algebra

the function W(d)=0.112d approximates the amount in centimeters of water that results from d cm of snow melting. Find the amount of water that results from snow melting from depths of 18 cm, 49 cm, and 98 cm. I am having problems figuring this out and I

57. physicssssss

A block with mass m = 14 kg rests on a frictionless table and is accelerated by a spring with spring constant k = 4545 N/m after being compressed a distance x1 = 0.515 m from the spring’s unstretched length. The floor is frictionless except for a rough

58. physicsssss

A mass m = 4 kg hangs on the end of a massless rope L = 2.02 m long. The pendulum is held horizontal and released from rest. 1)How fast is the mass moving at the bottom of its path? 2)What is the magnitude of the tension in the string at the bottom of the

59. physics

A proton moves from a location where V = 70 V to a spot where V = -31 V. (a) What is the change in the proton's kinetic energy? J (b) If we replace the proton with an electron, what is the change in kinetic energy?

60. Calculus

What is the limit of this function as x approaches 0? cos(x) - 1 / x From what I gather, the limit is equal to 0, since on the right, the function approaches from negative values close to zero and on the left, it approaches 0 with positive values close to

61. calculus

How many roots does the graph of this function have? 4x^4 - 4^x I believe that it either has two or three roots.

62. algebra

Simplify each expression. Justify your steps using the Commutative, Associative and Distributive Properties when necessary 8k2 + 4k - 3k2 + 3^2 - k + 5 Please let me

63. Chemistry

An aqueous solution of copper (I) chloride is 15.7% by mass copper (I) chloride. Copper (I) is 35.8% by mass chlorine. If the solution has a density of 1.045 g/cm³, how many gallons of solution contain 2.3 kg of copper? Trying to help my son study. Thank

64. Biomechanics

XY coordinates of the right toe of a soccer kick performer are Frame 20: (2.62, 0.99) Frame 14: (2,34, 0.16). How far did the toe travel in the upward direction between frames 14 and 20? How fast did the toe travel in upward direction between frames 14 and

65. physics

Vector is 6.3 units long and points along the negative axis. Vector is 9.0 units long and points at 55 to the positive axis. 1- What are the and components of vector ? 2-What are the and components of vector ? 3-Determine the magnitude of the sum .

A candidate for a political office claims that he will win the election. A poll is conducted, and 35 of 150 voters indicate that they will vote for the candidate, 100 voters indicate that they will vote for his opponent, and 15 voters are undecided. a.

67. Science (Lab)

So I have yo do a Lab for science (this is our very first lab, well we did a second one) & I really need help. This ia fictional lab experiment not a real one we are not really doing the experiment. Me 7 my group was doing it together we just have to do

Sam owns an acre of land on Red River. The government dams the river. A lake forms behind the dam, covering Sam's land. Does the government owe Sam anything? I don't want you to give me the answer but maybe just a reference where I could see the law on

69. physics

Vector (V1) is 6.3 units long and points along the negative (X) axis. Vector(V2) is 9.0 units long and points at 55 degree to the positive (X)axis. 1- What are the (X) and (Y) components of (V1) vector ? 2-What are the (X) and (Y) components of(V2) vector

70. Chemistry

An aqueous solution of copper (I) chloride is 15.7% by mass copper (I) chloride. Copper (I) is 35.8% by mass chlorine. If the solution has a density of 1.045 g/cm³, how many gallons of solution contain 2.3 kg of copper?

71. physics

Two particles with Q1 = 40 µC and Q2 = 87 µC are initially separated by a distance of 2.6 m and then brought closer together so that the final separation is 1.7 m. What is the change in the electric potential energy?

72. biology

Are the categories animallike, plantlike, or funguslike useful in classifying protists? Please explain.

73. maths

how many 3-digit numbers have exactly 2 digits that are the same?

74. mba

Find the maximum and minimum values of the following function. 8x3 – 75x2 + 150x

75. math

simplify the following by adding like terms -4-6m+10n-56-n+9m

76. calculus

What is the limit of the function as x approaches infinity? 4x^4 - 4^x Would the limit be positive infinity or negative infinity?

77. math

If 1 is less than a number is divided by 5 less than twice the number the result is 21over39 wat is the number? plsssssssssss answer!

78. calculus

What is the limit of the function as x approaches infinity? (x^4 - 7x + 9) / (4 + 5x + x^3) From what I know, the limit should be infinity since the greater exponent is in the numerator. However, I am only given the options: 0, (1/4), 1, 4, or Does not

79. algebra

In a real-life situation, to model the distance x and the height of hitting a baseball y as in: y = ax^2 + bx + c 1. When dealing with the initial height of the ball, what is happening when x = 0? Is it that the ball has not yet traveled any distance? 2.

80. Psychology

When a student took her psychology quiz, she did badly on the essay question. Ealier, she had written a good practic essay on this concept. The failure of which memory process led to her poor essay performance? A) Encoding B) Retrieval C) Repression D)

81. american history

Who belief in expansionism led to the building of the panama canal

82. math

the function it described by h(x)2.75x+71.48 can be used to predict the humerus (the bone from the womens elbow to the shoulder) is x cm long predict the height of a womens whose humerus is 39 cm long

83. physics

A car accelerates uniformly from rest to a speed of 55 km/h (15 m/s) in 14 s. Find the distance the car travels during this time.

84. Physics

Two point charges, +3.90 ìC and -7.50 ìC, are separated by 3.30 m. What is the electric potential midway between them?

85. Science

What is the wavelength and the frequency of a 50-MeV gamma ray photon.

86. Physics

Let vector A = 4i^ + 4j^, vector B = -2i^ - 5j^, and vector F = vector A - 5(vector B). a) Write vector F in component form. vector F = ? b) What is the magnitude of vector F? F = ? c) What is the direction of vector F? theta = ? Thank you!

87. Health

What is the average teen suicide rate in the state of New York, as well as the top five reasons (in order) for teen suicides there? Thanks :)

88. Physical Science

What kind of experiment might you use to distinguish between a gamma ray of wavelength 10^-11m and an electron whose de Brogile wavenlength is also 10^-11m?

89. physicssss

A mass m = 73 kg slides on a frictionless track that has a drop, followed by a loop-the-loop with radius R = 17.9 m and finally a flat straight section at the same height as the center of the loop (17.9 m off the ground). Since the mass would not make it

Which is an effective strategy for ending an informative letter to a new client? A. stress that the reader is welcome to call anytime if more information is needed. B. Refer to your company's future relationship with the readee's organization. c. Mention

91. Chemistry

Thank you so much for the help on my other question!!! An alloy (solution of metals) is 80% by volume iron. The rest is aluminum. Aluminum has a density of 2.70 g/cm³, and iron's is 7.87 g/cm³. A block of alloy measures 2.0 ft. wide and 3.0 ft. long. If

92. College biology

In testing synaptic transmission, you found that there were 300 failures in 1000 trails of stimulating a presynaptic neuron. The average EPSP size was .7 mV +/- .2mV (mean +/- SD), and the average 'mini' EPSP size was .6mV +/- .1mV. Does the synapse obey

93. physics

a gun fires a shell with a speed of 315m/s. Neglecting the effects of air resistance, calculate the maximum range of this gun

94. Accounting

I have added Below my balance sheet and income statement now the statement of owners equity is the beginning capital 28,2800 plus the net income 21,550 which is 49,750 less withdrawals 5,000 equals 44,750 which does not equal my assets. I cannot figure out

95. Physics

Given the vector from the pivot point to the force and the magnitude of the force. 1.How would one find the angle of the force? 2.How would one find the torque? 3.How would one calculate the maximum/minimum torque?

96. GCSE-enviromental studies

please could someone help me answer theses questions. 1)why is Braunton Burrows in North Devon a biosphere reserve? 2)the kind of habitats that are present in Braunton Burrows 3)what activities are carried out at in the reserve 4)How and why the reserve is

97. physical

What is the wavelenght if the distance covered by a wave in 14 succesive trough is 25cm

98. Calculus

Find lim [f(x+h)-f(x)]/h h->0 f(x) = 2 - 5x + x^2

99. physical education

in what all tips does physical education help?

100. algebra

why are these equations poor models of hitting a baseball: y= -0.002x(x-433.1) I get maximums of (216,93). Other problems' maximums are in the (220, 100)range. So are they poor models because the distance and heights are unreasonable? 2) Why is the

101. Calculus

Find the indicated limits. If the limit does not exist, so state, or use the symbol + ∞ or - ∞. f(x) = { 2 - x if x ≤ 3 { -1 + 3x - x^2 if x > 3 a) lim 3+ f(x) x->3 b) lim 3- f(x) x->3 c) lim f(x) x->3 d) lim ∞ f(x) x->3 e) lim -∞ f(x) x->3

102. Calculus

Find all points of discontinuity f(x) = [x^2 + 5x - 2]/ [x^2 - 9]

103. Calculus

If f(x) = { √2-x x < 2 { x^3 + k(x+1) x ≥ 2 determine the value of the constant k for which lim exists. x->2

104. geometry

how do you justify if three lenghs make a triangle?

105. Statistics

Given IQ~N(100, 256) find P(IQ > 115). Be certain to set your calculator to FLOAT 4 to match my answer exactly. I need to know how to figure this out on my calculator.... no one has taught me how to use my calc and I am so confused.... someone please help!

106. mathematics

Simplify the expressions 1.) Cos^2x/sin^2x + csc x sin x 2.) (Sec x +1)(sec x - 1)

107. Chemistry

Element X has three istotopes, X⁹⁵, X⁹⁶, and X⁹⁸. Element X has an atomic mass of 96.344u. If X-98 has a mass of 98.0001u and an abundance of 19.8%, what are the abundances of X-96 (mass of 95.9988u) and X-95 (mass of 95.0011u)?

108. math

Prove that the equation Is an identity. Sec^4x - Tan^4x = Sec^2x + Tan^2x

109. Home insurance

Disability insurance is designed to replace: A.Damageed property B.loss or damage to property C.money damages awarded in a law suit against you D.lost income i got B.

110. physics

Vector is 6.3 units long and points along the negative axis. Vector is 9.0 units long and points at 55 to the positive axis. 1- What are the and components of vector ? 2-What are the and components of vector ? 3-Determine the magnitude of the sum .

111. Statistics

Each year, thousands of college seniors take the Graduate Record Examination (GRE). Assume the scores are transformed so they have a mean of 600 and a standard deviation of 150. Furthermore, the scores are known to be normally distributed. Determine the

112. Physics

A person walks 28.2◦ north of east for 3.33 km. Another person walks due north, then due east to arrive at the same location. How far due north would this person walk?

113. REPORT- HELP ME

I want to know what needs to create a report on the contents of the subject problem solving .. lecture want us to write report every time after class runs out .. report on the subject that we learned during class that day ..so I want know what needs to be

114. math

Simplify the expression. 1.) (Sec x +1)(sec x - 1)

115. C1

THE LINE V PASSES THROUGH THE POINTS(-5,3)&(7,-3)&THE LINE W PASSES THROUGH THE POINTS (2,-4)&(4,2).THE LINE V&W INTERSECT AT THE POINT A.WORK OUT THE COORDINATES OF THE POINT A

116. world problem MATH

the temperateure of Mars reaches 27 degree celsius during the day and -125 degree celsius at night. What is the average temperature? can youhelp me do this problem i am not sure.

117. Algebra

How do I solve these equations? I was out sick a whole week :( please no direct answers. I want to know the process as well. -a=5 4/5x=20 -2/3y=-18 -x/3=18 Please note that the / are fractions. Thank you so much in advance!! :)

118. Math - fractions

I have to find the area of a rectangle in fraction measurements. Area = L*W = 9/16 yds. * 14/15 yds.

119. Math

Expressions please help p less than 5 p greater than 10 9 times the sum of p and 6

120. curriculum development project

My topic is community and I have to form a paragraph from the 10 activity plans such as math, science literacy, dramatic play, language and literature, puppets, music and movement, sensory centers, art, science and social studies. the paragraph consist of

121. Math

Please show work. 9 1/10 + 7 2/5

122. SHSAT-URGENT

Can someone please give me a link for a website or websites that provide shsat student handbooks-other than 2011-2012 and 2010-2011. thank soo much in advance i only have a few more weeks to study and have no resouces please.

123. organic chemistry

(x/15)/[(1.5-x)/45]=5.8 how do I move these around to find x partition coefficient equation

124. Calculus

Find the points of discontinuity. f(x) = { 16/x^2 if x ≥ 2 { 3x - 2 if x < 2

125. algebra

So if the distance and height are reachable, why are these equations poor models of hitting a baseball: y = -0.5x^2 + 216x + 3 y = -0.002x^2 + 0.879x + 3.981 y = -0.002x^2 + 0.8732x - 3.981

3. To assist in evaluating written communications skills in the employment process, many managers include as a requirement: (Points : 5) handwritten applications. essay-type questions. application forms. portfolios.

127. chemical

The vapor pressure of mercury at 77¢K is 0.0018 mmHg. The atomic weight of mercury is 200.6 g/mole. If the mercury vapor were allowed to reach equilibrium at this temperature in an enclosed space, what would be the mercury vapor concentration in the

128. Applications of Multipication

A convenience store sells 1650 items where 12/25 of the items are junk food. How many of the items are junk food?

129. Chemistry

If 0.1g of Unknown chloride reacts with 0.164 g of AgNo3 to form 0.05g of Agcl and unknown Nitrate.How do we find Unknown chloride?

130. math

-x+5y=1 2x+4y=-4

131. math

33 1/3% of what number is 26.5?

9. "Basic essentials" is an example of a: (Points : 5) cliché. redundancy. doublet. trite phrase

133. math

66 2/3% of what number is 76.2

134. math

\$63 is what % of \$84?

135. math

what % of 480 is 270?

136. university studies

How have you used these actions to solve problems in your daily life? How are critical thinking skills in your daily life and in your academic life similar? How are they different?

asked by us 101 week 9 DQ 3
137. College biology

In testing synaptic transmission, you found that there were 300 failures in 1000 trails of stimulating a presynaptic neuron. The average EPSP size was .7 mV +/- .2mV (mean +/- SD), and the average 'mini' EPSP size was .6mV +/- .1mV. Does the synapse obey

138. College biology

In testing synaptic transmission, you found that there were 300 failures in 1000 trails of stimulating a presynaptic neuron. The average EPSP size was .7 mV +/- .2mV (mean +/- SD), and the average 'mini' EPSP size was .6mV +/- .1mV. Does the synapse obey

139. Algebra

Hi. I've tried doing these problems and got long decimals that don't make sense. Please help!! 1) 13x + 6=4x-4 2) (1/2)x + 8= 3x + 2 3) (n/3) + 8=n + 1 4) 2n + 3= 2n + 3 I don't know how I would find n in this one!! 5) 5x + 2(2x-1)=-16 Thanks so much for

140. accounting

I have figured this out I just want to make sure I am correct in my answers. 1.On January 2, 2007, A company issued \$100,000 of 5%, 10 year bonds. The bonds will mature in ten years. The bonds were sold for for 95% (or .95 of par) and will pay interest

141. math

Prove that the equation Is an identity. Sec^4x - Tan^4x = Sec^2x + Tan^2x

142. ETH125

Did African Americans go through annexation?

143. calculus

What is the limit of this function as x approaches infinity? 2^x + x^3 / x^2 + 3^x

144. physics

Let's assume you use green light (λ = 550 nm) to look at an electron. What is the uncertainty in determining the electron's velocity? Express your answer rounded up to the nearest hundredth.

145. human service

I am having problems with finding an example of how an organization can use organizational commitment to positively impact job satisfaction. Can you give me any ideas of where to find information.

146. chemistry

what are some experimental observations which support the theory that there is restricted rotation around double bonds? I know it would require more energy to breakthe pi bonds so maybe higher melting point? I can't think of anything else really.

147. maths

In a game of skill, a player has probability 1/3,5/12,1/4 of scoring 0,1,2 respectively and the game ends when he scores a zero. Assuming independence of trials, find the probability of the total score being 'n' when the game ends?

148. geometry

find the value of x and y of a parallelogram one side a degree

149. PHYSICS

A positive charged particle placed on a frictionless table by attaching it to a string fixed at one point of magnetic field is switched on in the vertical direction, the tension in the string (A) will increase (B) will decrease (C) will remain same (D) may

150. Chemistry-thanks

I have a method using HPLC (high performance liquid chromatography). It states that a 4.6 x 150mm,3um column should be used. (stationary phase : octadecylsilyl silica gel). I have a 4.6 x 100mm,2.7um column, silica-based, bonded-phase (non-polar) column.

151. buss/stats

what is it called when all the items in the population have the same chance of being selected for the sample?

152. Math

julia needs to purchase a ladder that just reaches the top of a 16 foot building. if the bottom of the ladder will be placed 12 feet from the base of the building how long should julia's ladder be?

153. physical

What is the wavelenght if the distance covered by a wave in 14 succesive trough is 25cm

154. Calculus

If the slope is 3, find an equation of the tangent line to the curve at P(8, -3).

155. Calculus

Find the Limits. lim [t^3 + 3t^2]/[t^3 - 4t^2] t->0

156. probability

find F(y) and f(y) if Y=-4X+3 and f(x)=2(e^-2x)u(x)

157. Science

How is our water resources connected with the economical conditions of our country? Please explain to me.

158. mathssssss

If (2x-3) is a factor of 2x raised to the power four-3xsquare+15x-15k,find the value of (3k-root 5 k).

159. Chemistry-help needed

Posted by angie on Saturday, October 8, 2011 at 6:02am. I have a method using HPLC (high performance liquid chromatography). It states that a 4.6 x 150mm,3um column should be used. (stationary phase : octadecylsilyl silica gel). I have a 4.6 x 100mm,2.7um

160. chemistry

what is the new boiling point for a solution prepared from 1.40 mol of KCI 1.00kg of water?

161. algebra

Suppose the ball was 2.74 feet above ground when it was hit. It reached a max. height of 116.3ft when it was approx 215.3 ft away from where he hit the ball. The ball lands after travelling a ground distance of approx 433.1 ft. -- find an equation in form

162. organic chemistry

(x/15)/[(1.5-x)/45]=5.8 how do I move these around to find x partition coefficient equation

163. math

Arthur can paint a room in 6 hours. Boris can paint the same room in 8 hours. If boris and arthur work together, how long will it take for them to paint the room

164. algebra

Find the length of one base of a trapezoid if the area is 126 inches squared, the height is 7 inches and the length of the other base is 15 inches.

165. healthcare

required annually pap smear: government is limiting those who have medicaid only to recevie the pap smear only every 3rd year but those you have private insurance it will cover it annually . what do you think opinions

166. Statistics

Classify the following variable as nominal, ordinal, discrete, or continuous and state why it is such a variable: number of US Senators

167. eng 102

I need help picking out a topic to write about. this is the assignment. analyzes a current problem in light of a historical event/situation and primarily argues a truth claim( definition, cause-and-effect, and/or resemblance)

168. Chemistry

Element X has three istotopes, X⁹⁵, X⁹⁶, and X⁹⁸. Element X has an atomic mass of 96.344u. If X-98 has a mass of 98.0001u and an abundance of 19.8%, what are the abundances of X-96 (mass of 95.9988u) and X-95 (mass of 95.0011u)?

169. Chemistry

Element X has three istotopes, X⁹⁵, X⁹⁶, and X⁹⁸. Element X has an atomic mass of 96.344u. If X-98 has a mass of 98.0001u and an abundance of 19.8%, what are the abundances of X-96 (mass of 95.9988u) and X-95 (mass of 95.0011u)?

170. us history

President Roosevelt helped end the Russo-Japanese war with which one of these? The Great White Fleet; Gentlemen's agreement ; spheres of infuence ; or the treaty of Portsmouth

171. Calculus

Recall that the average velocity between times t1and t2 is calculated using vave = y(t2) − y(t1)/t2 − t1. We are given that y = 14t − 1.86t^2. Evaluating at t = 1, we have y(1) = 14(1) − 1.86(1)2 = 12.14. Thus, the average velocity between times 1

172. PHI 103

an argument with a friend, family mem ber or a co-worker in premis-conclusion