1. Chemistry

According to the quantum-mechanical model for the hydrogen atom, which of the following transitions would produce light with longer wavelength: 3p to 2s or 4p to 2s? A) The 3p to 2s transition would produce light with longer wavelength. B) The 4p to 2s

2. math

It takes 8 hours for one crew to clean an office building. It takes a second crew 10 hours to clean the same building. If the first crew works 2 hours and leaves and the second crew takes over to complete the job, how long will it take the second crew to

3. Algebra

The formula I = PRT where I = Interest, P = principal, R = rate, and T = time is used to calculate the amount of simple interest earned. Solve this formula for T.

4. Chemistry

A Solution Has A PH Of 3.4.What Is Its Hydrogen Ion Concentration?

5. Physics

A football quarterback shows off his skill by throwing a pass 45.90 m downfield and into a bucket. The quarterback consistently launches the ball at 40.00 ∘ above horizontal, and the bucket is placed at the same level from which the ball is thrown. What

6. physics

If a 5kg object experiences a 10 N force for a duration of 0.10 second then what is the momentum change of the object.

Wallpaper was applied to one rectangular wall of the photographer s studio. .The dimension of the wall are shown below 42 ft by 25.5 feet .If the total cost of the wallpaper was &771.21, what was the cost of the wallpaper per square foot.

8. Maths

A rectangle measuring 7cm by 4cm is enlarged by ratio 2:1? a)what's area 1)the original reactangle 2)the enlarged rectangle b)by what ratio has the area been enlarged

9. PHYSIC

A bullet is fired in a horizontal direction with a muzzle velocity of 300m\s in the absence of air resistance,how far will it have dropped in travelling a horizontal distance of (a)20m (b)40m (c)60m (d)how far will it drop in one second

10. physics

The pressure of water on the ground floor is 40,000 Pascal, and at the first floor is 10,000 pascal. Find the height of the first floor.

11. Chemistry

Calculate the wavelength, in nanometers, of the spectral line produced when an electron in a hydrogen atom undergoes the transition from the energy level n = 2 to the level n = 1.

12. math

Fishing hook E is dropped 2.5 times its present depth. where is fishing hook E now? NOTE: FISHING HOOK E is -7.1 is the answer -4.14 or -17.75

13. History

How did George Mason influence the creation of Bill of Rights? A.He refused to sign the United States Constitution. B.He encouraged others to opposed the ratification of the Constitution. C.He assembled a anti-federalist convention in Virginia to discuss

14. Present Value Math

Find the present value of an ordinary annuity of \$500 payments each made quarterly over 6 years and earning interest at 8% per year compounded quarterly. ​ \$9,456.96 \$2,311.44 \$24,968.07 \$5,264.38 Thank you

15. Chemistry, que 10

How many atoms are present in one formula unit of calcium hydrogen carbonate Ca(HCO3)2? Could someone explain to me why the answer is 11? Thank you.

As a fringe benefit for the past 8 years, Colin's employer has contributed \$50 at the end of each month into an employee retirement account for Colin that pays interest at the rate of 8%/year compounded monthly. Colin has also contributed \$2,000 at the end

17. Math

Pierce Publishing sells encyclopedias under two payment plans: cash or installment. Under the installment plan, the customer pays \$23/month over 2 yr with interest charged on the balance at a rate of 15%/year compounded monthly. Find the cash price for a

18. English

Which of the following quotes from Adventures of Huckleberry Finn contains a metaphor? A:"Look at it, gentlemen and ladies all; take a hold of it;shake it. There's a hand that was the hand of a hog; but it ain't so no more; it's the hand of a man that's

19. Math Homework

The following frequency table contains the total number of deaths worldwide as a result of earthquakes from 2000 to 2012. Year Deaths 2000 231 2001 21,357 2002 11,685 2003 33,819 2004 228,802 2005 88,003 2006 6,605 2007 712 2008 88,011 2009 1,790 2010

20. Science

suppose a skydiver (mass = 75 kg) is falling toward the earth. when the skydiver is 100 m above the earth he is moving at 60 m/s. at this point calculate the skydiver's

21. physics

What is the pressure of the water in pascals at the bottom og a lake which is 5 meters deep?

22. Algebra

Mickey charges \$15, \$30, \$45, and \$60 for babysitting 1, 2, 3, and 4 hours, respectively. Is the relationship between the number of hours and the amount charged porportional? If so, find the unit rate. If not, explain

23. science

An object is placed at a distance of 12 cm from a concave mirror of radius of curvature 16 cm .find the position of the mirror.

24. Math Physics Torque Equilibrium

A uniform meterstick pivoted at its center has a 100 g mass suspended at the 21.0 cm position. At what position should a 95.0 g mass be suspended to put the system in equilibrium? What mass would have to be suspended at the 80.0 cm position for the system

25. Math

Find the accumulated amount A if the principal, P = \$3700 is invested at the interest rate r = 7%/year for t = 12.5 years compounded semiannually. Round your answers to two decimal places. ​ a. The accumulated amount is \$8544.01. b. The accumulated

26. physics

The center of a 1.00km diameter spherical pocket of oil is 1.00kkm beneath the Earth's surface. Estimate by what percentage g directly above the pocket of oil would differ from the expected value of for a uniform Earth? Assume the density of oil is

27. Describing Data

The following frequency table contains the total number of deaths worldwide as a result of earthquakes from 2000 to 2012. Year Deaths 2000 231 2001 21,357 2002 11,685 2003 33,819 2004 228,802 2005 88,003 2006 6,605 2007 712 2008 88,011 2009 1,790 2010

28. math

The value of a car decreases at a constant rate. After 1 year the value of the car is \$20,000. After 2 more yearsit is \$14,000. Write an equation in slope-intercept that represents the value y (in dollars) of the car after x years.

29. MATH HELP PLEASE I HAVE NEVER BEEN MORE CONFUSED

The value of a car decreases at a constant rate. After 1 year the value of the car is \$20,000. After 2 more yearsit is \$14,000. Write an equation in slope-intercept that represents the value y (in dollars) of the car after x years.

30. Repost(Physics)

A vehicle moves in a straight line with an acceleration of 2 km/h^2. By how much does the speed change each second? Answer in units of km/h. Plz help?

31. Measures of Central Tendency

The table below shows the scores of a group of students on a 10-point quiz. Test Score Frequency 3 0 4 2 5 2 6 1 7 2 8 3 9 0 10 4 The mean score on this test is: The median score on this test is

32. BioChemistry

how many moles of estradiol (mw = 272) are there in 2 ml of a 100 μm solution

33. math

Fishing hook G is let down 2 1/2 times its present depth. where is fishing hook G now? FISHING HOOK G = -6 2/3

34. math

The value of a car decreases at a constant rate as it grows older. When the car is 2 years old, it is worth \$23,000. When the car is 5 years old it is worth \$15,500. Write and equation relating y (value of the car \$) to x (age of car).

35. math

a gardner having 150 meters of fencing materials wishes to enclose a rectangular plot of land and also erect a fence across the land parallel to two of the sides.find the maximum area he can enclose

36. bctc

A tank of water in the shape of an inverted cone is being filled with water at rate of 12m^3/min. the base radius of tank is 26 meters and the height of the tank is 8 meters. at what rate is the depth of the water in the tank changing when the rains os the

37. Physical

A motor car travelling at 14m/s on dry flat surface should be able to stop in 14m.Assuming the deceleration to be uniform. Given: its value and the corresponding bracking time is -7m/s^2 , 2 sec Calculate the distance travelled during the first second

38. Algebra

One alloy of brass is 70% copper and 30% zinc. Another alloy of brass is 40% copper and 60% zinc. How many grams of each of these alloys need to be melted and combined to obtain 300 grams of a brass alloy that is 60% copper and 40% zinc

39. math

The value of a car decreases at a constant rate. After 1 year the value of the car is \$20,000. After 2 more yearsit is \$14,000. Write an equation in slope-intercept that represents the value y (in dollars) of the car after x years. What is the y-intercept

Find the present value of an ordinary annuity of \$1,400 payments each made semiannually over 8 years and earning interest at 12% per year compounded semi-annually. ​ \$6,954.70 \$9,763.58 \$14,148.25 \$3,365.99 Thanks for the help

41. Physics

A vehicle moves in a straight line with an acceleration of 2 km/h^2. By how much does the speed change each second? Answer in units of km/h. Plz help?

42. Math

A car rental agency charges ​\$35 per day to rent a car and ​\$14.95 per day for a global positioning system​ (GPS). Customers are charged for their full tank of gas at ​\$3.40 per gallon. A car has a 19 gallon tank and a GPS. a) Write a function rule

43. English

1. This is where I live. 2. Tell me where he lives. 3. Will you tell me why he was late. 4. Do you know how he solved the problem. 5. I remember when he arrived. ------------------------------ There are where, why, how, when in the sentences. Which ones

44. science

A flywheel makes 120 rpm. Find the angular speed of any point on the wheel and linear speed of a point is 10 cm from the center of the wheel.

45. physics

Calculate the mass of moon if free fall acceleration near it surface is know be 1.62 m/s^2 ( radius of moon is 1738 Km )

46. Algebra

Country A has a growth rate of 4.7% per year. The population is currently 5,646​,000 and the land area of Country A is 13​,000,000,000 square yards. Assuming this growth rate continues and is​ exponential, after how long will there be one person for

47. Physics

I've been stuck on this questions for 2 days A 7.2-kg bowling ball traveling at a speed of 3.5 m/s collides with a 1.2-kg bowling pin at rest. After the collision, the pin moves with a speed of 3.0 m/s at an angle of 60° with respect to the original

48. Physics

An astronaut with mass M floating at rest in the International Space Station catches a spinning frisbee that someone has thrown directly towards his or her center of mass. The frisbee has a mass m, a radius r, a moment of inertia of ⅔ mr2, and had a

49. Science

A screwdriver with the one similar shaft in a 4 cm handle is used to tighten a screw the mechanical advantage is

50. Chemistry

What happens to an atom when it absorbs energy? 1) The atom stores the energy for later use. 2) The atom re-emits the energy as electromagnetic radiation. 3) The extra energy increases the speed of the electrons in their orbitals. 4) The extra energy

51. Chemistry

0.3975 g of an oxide of divalent metal on reduction with hydrogen gives 0.090 g of water. The atomic weight of metal is: a) 63.5 b) 24 c) 55.5 d) 40

52. physics

If the systolic blood pressure is 120mmHg, what is the pressure in lb/in^2 and in pascals?

53. Physics

A 1.11 kg toy train rolls around a circular horizontal track. If the train has an angular acceleration of -2.2 rads/s2 and is released with an angular speed of 17.0 rpm, what time is required for the train to come to a complete stop?

54. Physics

Can you find a vector quantity that has a magnitude of zero but components that are different from zero? Explain.

55. CALCULUS

if F(x) = f(xf(xf(x))),where f(1) = 4, f(4) = 6, f '(1) = 4, f '(4) = 5,and f '(6) = 6,find F '(1).

56. math

A bird beats it's wing 24 times per second. How many times will it beat it's wing in one hour

57. English

1. Did you know? + Where did he go? => Did you know where he went? 2. Did you think? + Why was he late? => Did you think why he was late? => Why did you think he was late? - I thought he was late because he got up/gotten up late. 3. Did he know? + When did

58. science

Mass of 48.176 * 10raze to power 23 molecules of CH4 will be

59. Calculus

An error in the measurement of the radius of a circle results in an error in the computation of its area. Find and interpret the sensitivity of area (a) of a circle to the measurement of radius, r, when the radius r=2 meters.

60. Math (Calculus)

Determine if each of the following functions is in Big-O, is Big-Omega and is Big-Theta of x: (Could be multiple) a) f(x)=10 b) f(x)=3x+7 C) f(x)=x^2+x+1 d) f(x)=5log(x) e) f(x)=|x| f) f(x)=x/2 I'm in calc 1 and I have no idea what's it even asking me.

61. Chemistry

A chemist reacted 0.05 mol of sodium with water to form 50cm3 of sodium hydroxide what was the mass of sodium reacted Na+h2p-Noah+h2

62. Biochemistry

You wish to make 3 reactions (1 ml each) with the specified amounts of protein. The remainder of each reaction consists entirely of buffer. The source of your protein is a stock solution that has a concentration of 0.5 mg/ml. What is the volume of stock

63. English

1. Do you know? + Can he play the piano? 2. Do you know if/whether he can play the piano? 3. Do you think? + Is he still alive? 4. Do you think if he is still alive? * 4-1. If do you think he is still alvie? 5. Do you think he is still alive?

64. English

1. I bought a ball-point pen at the stationery store. 2. I bought a ballpoint pen at the stationery store. 3. I bought a ball pen at the stationery store. 4. I bought a ballpen at the stationery store. 5. I bought a ball point at the stationery store. 6. I

65. Chemistry

The principal quantum number (n): 1) specifies the subshell of the orbital. 2) specifies the principal shell of the orbital. 3) specifies the 3-D shape of the orbital. 4) specifies the maximum number of electrons. 5) none of the above

66. algebra 1

by the end of your 6th Spanish lesson you have learned 20 vocabulary words. when you started (0 lessons) you only knew 2 words. write an equation that gives the number of vocabulary words you know, y, in terms of the number of lessons you have had, x. (iv

67. english

"They have arried in the Land of opportunity and the opportunities are swirling dizzily promiscuously around them" Is this quote suppose to have a negative connotation? The passage I got it from is about someone arriving to America and being disappointed

68. Chemistry

The heat of combustion of C2H4 at 27 C at constant prssure is -333.3 Kcal. What will be the heat of combustion at constant volume considering the water to be in liquid state? (R=1.987 cal)

The photographer wants to display her photograph in her studio A wall in her studio is 10 ft wide .She wants each picture to be 3 feet apart .If she displays photographs that are 4"wide by 6" high . How many photographs can she display side by side on her

70. Math

A shopper keeper sold a total of 15 boxes of pencils on Monday and Tuesday. She still three more boxes on Monday then on Tuesday. There were 12 pencils in each box. How many pencils did she sell on Monday?

71. physics

Question 6) Oil and gas exploration companies find new underground deposits by measuring (with incredible precision) the value of g at the Earth's surface. EXTRA INFO GIVEN: The challenge: F=Gm1m2/r^2 ONLY works for two cases: point masses, or if one of

72. Chemistry

What pressur would the propane gas sample have at 75Ml

73. Grammar

Is the word "bring" a linking verb?

74. math

A model car travels horizontally after being released. The car travels a distaance d metres in a time of t seconds. d is directly proportional to t. The car travels 20 metres in a time of 2 seconds. A.Calculate the distance the car travels in 3 seconds.

75. Physics

Can you find two vectors with different lengths that have a vector sum of zero? What length restrictions are required for three vectors to have a vector sum zero? Explain.

Find the sum of first thirteen terms of a linear sequence whose 8th term is 18 and 11th term is 24.

77. Physics

A 500-kg disk-shaped nonrotating satellite gets hit by a 5-g piece of space debris moving at 1 km/s. If the debris buries itself near the satellite’s rim, how rapidly will the satellite rotate after the hit?

78. English

1. I think you are not serious, are you? ..................................... Does 'serious' mean 'injured severely'? ======================================= 2. I don't think he is serious, is he? (Does 'serious' mean 'thoughtful' or 'injured badly'

79. Kumar

C6H6-O-CH2-C6H6 + HI

80. Physics

in the laboratory frame, a photon of energy 8.0 x 10^3 eV and a free electron of energy 2.0 x 10^3 eV (consider what is meant by 'energy' here; is it kinetic energy? total energy? can it be total energy?) are moving directly towards each other and collide

81. Math

If there are 35 kids in a class and 22 are girls what is the ratio of girls to boys in the class

82. Math

12(p-2 1/3)=-8

83. math (horizontal tangent line)

Determine the point(s) if any at which the graph of the function has a horizontal tangent line. y=x^3+x I graphed this function out and it looks like there isn't any horizontal tangents. Am I correct or am I forgeting something? I tried finding the

84. Math

2(p-2 1/3)= 12

85. Physics

A 51.6 g box is left 17.8 cm from the centre of a merry-go-round. If the box has coefficients of friction of μs = 0.790 and μk = 0.480 with the merry-go-round, what is the maximum speed of the merry-go-round without having the box slide off of the

86. Math

What is the distance between 86.25 to -17.75

87. English

What Is Annoying

88. Eng

Wath Is Diplomat

89. Chemistry

Find the frequency if given energy 6.3x10^-19 Do I use the formula E=hf? 6.3x10^-19=6.626x10^-34(f) Then do I divide E and H?

90. math

design a container box yhat can be able to hold 15pieces of 4g candiy and has a parabola as the main theme of the design. use the correct mathematical equation in solving for the dimensions of the container.

91. Math

A car rental agency charges ​\$35 per day to rent a car and ​\$14.95 per day for a global positioning system​ (GPS). Customers are charged for their full tank of gas at ​\$3.40 per gallon. A car has a 19 gallon tank and a GPS. a) Write a function rule

92. English

1. This is the way by which he passed. 2. This is the way. He passed by the way. (Are both correct? If the two sentences in #2 are combined, can we get #1?) 3. This is the way by which he could understand the situation. 4. This is the way. He could

93. integrals

why cant we just use power rule for this 1/((x^2+4))^2

94. english

Chinua Achebe's Things Fall Apart as a defiance of eurocentric sociological and anthropological narration of South Africa

95. science

Now what happens if your feet hit a slippery spot on the ground? your feet slip and the (blank) cant exert as much force back on you.

96. Physic

Point B is 5.0 KM east of Point A. A cyclist leaves A and goes 3.0 km in a direction of 30 degrees to the north of east A. in what direction mus the rider go from this point to reach point B? B. what distance must be covered? please explain

97. Math

2.6(m+1.9)=6.5 Solving equations involving distributing property

98. Science

an object of mass 2 kg is dropped from a certain height.On rebounding from the ground,it rises vertically till 2/5th of its initial height.what will be the ratio of magnitude of momentum of the object just before and after striking the ground?

99. Math, Functions

If g(t)= 1/t-2-1, how to solve g(t)=0 ...? Please teach me..!

100. Math, Functions

What is the Domain and Range of the function f(x)=2x+1 ? Please teach meeeee!

101. math

4. Thomas is at a store buying school clothes. T-shirts are on sale for \$13 each and jeans are on sale for \$18 each. a) Write an equation that represents the total cost for x T-shirts and y pairs of jeans. I need help with a.. b) Thomas bought six T-shirts

102. math

1 1/2(n-4 1/2)=12 Solving equations involving the distributing property

103. physics

The water tank is 8 m above the tap. What pressure forces the water out from the tap?

104. Physics

If vector A×vector B=0,does it necessary follow that A=0 or B=0? Explain.

105. Accounting

during 2016 bava corporation sold merchandise for a total of 600000 the cost of merchandise to bava was \$450000 bava offers credit terms of 1/10, n/30 to encourage early payment. at year end there are \$15000 of sales still eligible for the 1% discount.

106. Chemistry

calculate the mass ratio of 25% cacl2 solution and water to prepare 500 g of a 5% salt solution

107. Math

Write two that have given absolute value of 4,38,260,4092?

108. Math, Functionsons

What is the domain and range of the function f(x)=x^2-2? please teach me..!

109. Calculus

Can you please help me find the x and y intercepts of this equation. How do I solve this? y= x^2 √9-x^2

110. bctc

Suppose that 3 ≤ f '(x) ≤ 5 for all values of x. prove that 18 ≤ f(8)-f(2) ≤ 30 ?

111. Computer

Please give me an example of websites that are good for academic work..! What is the thing have in common??

112. Cost Accounting

What effect can an increase in production volume has on per unit fixed costs, per unit variable costs, total fixed costs, and total variable costs?

113. Chemistry

In a reversible reaction PCl5 ↔ PCl3 + Cl2, the value of K is 2.5. What will the partial pressure of Cl2 be?

114. physics

I have put a 100 gram weight ball in a plastic bottle and weight of this bottle is 20 gram .Now I shake this bottle in horizontal direction towards 5 centimeter back and forth with the applying force of 1 newton .So what will be the kinetic energy of this

115. cal

If h(x) = (4 + 3f(x))^(1/2) ,where f(3) = 4 and f '(3) = 3,find h'(3).

116. Physics

Is it possible that resultant of two vectors e smaller than the smaller of the two vectors?

117. physics numerical

A 15 g bullet is fired from a gun of mass 2kg with a speed of look m/s . Find the recoil velocity of the gun.

118. Science

Give reason-why current pass through the water

119. Math

Suppose you want to fence in a field, and then subdivide it into three equal parts. You have 2400 yards of fencing material to use. What should be the dimensions of one of the three smaller fields, if you want to fence in the maximum area?

120. special education

Which children (not just gender) with ADHD are least likely to be identified as having it?

121. math

A line has a slope of -6 that passes through the point (-12,5). What is the equation of the line? a. 6x + y = -77

122. english

Chinua Achebe's Things Fall Apart as a Postcolonial novel