# Questions Asked onNovember 23, 2012

1. ## Math

The population of a southern city follows the exponential law. If the population doubled in size over 13 months and the current population is 30,000 what will the population be in 5 years from now?

2. ## chemistry

The following soluble salts are strong electrolytes. For each, write a balanced equation for their dissociation in water. a. LiBr b. NaNO3 c. FeCl3 d. Mg(NO3)2

Which cannot describe a system of linear equations? no solution exactly two solutions infinite solutions exactly one solution I thought it was A or D but someone else is telling me it is B...no I'm confused...I thought it was 2 or more solutions

4. ## Chemistry

A 0.02882 g sample of gas occupies 10.0-mL at 288.5 K and 1.10 atm. Upon further analysis, the compound is found to be 38.734% C and 61.266% F. What is the molecular formula of the compound? What is the geometry shape around each carbon atom? Polar or

5. ## Pre-Calculus

A ball is thrown vertically upward with an initial velocity of 64 feet per second. The distance(in feet) of the ball from the ground after t seconds is s=64t-16t. At what time will the ball strike the ground? For what time t is the ball more than 28 feet

6. ## physics

Linearly polarized light is incident on a piece of polarizing material. What is the ratio of the transmitted light intensity to the incident light intensity when the angle between the transmission axis and the incident electric field is (a) 30° and (b)

7. ## Physics

Neutron stars consist only of neutrons and have unbelievably high densities. A typical mass and radius for a neutron star might be 5.8 x 1028 kg and 1.5 x 103 m. (a) Find the density of such a star. (b) If a dime (V = 2.0 x 10-7 m3) were made from this

8. ## science

Represent this reaction with balanced chemical equation. Disilane gas (Si2H6) undergoes combustion to form solid silicon dioxide and water.

9. ## microeconomics

. Suppose that two players are playing the following game. Player 1 can choose either Top or Bottom, and Player 2 can choose either Left or Right. The payoffs are given in the following table: Player 2 Player 1 Left Right Top 9 4 2 5 Bottom 1 0 3 1 Where

10. ## Math

Find the effective rate corresponding to the given nominal rate. (Round your answer to the nearest hundredth of a percentage point.) (a) 4%/year, compounded quarterly ? % (b) 3%/year, compounded monthly ? %

11. ## Maths

An aeroplane leaves a point on latitude 54degree south at 10 a.m. It flies due south at a steady speed of 800km/h. (a) what is its latitude at mid-point? (b) at what time does it pass over the south pole?

12. ## Chemistry

a stock solution of perchloric acid is 75.5% perchloric acid and has a density of 1.67g/ml. What is the molarity of the solution?

13. ## statistics

In a sample of 200 people, 154 said they watched educational television. Find the 90% confidence interval of the true proportion of people who watch educational television. If the television company wanted to publicize the proportion of viewers, do you

14. ## Math/statistics

a recent study indicated that 29% of the 100 women over age 55 in the study were widows. a. How large a sample must you take to be 90% confident that the estimate is within 0.05 of the true proportion of women over age 55 who are widows? b. If no estimate

15. ## Maths2

A plane leaves an airport X,20.6degree east and 36.8 degree north,and flies due south along the same longitude for 8hrs at the rate of 1000km/h to another airport Y,20.6 degree east and tita degree south.the plane then flies west to another airport Z for

A. random sample of 50 four year olds attending daycare centers provided a yearly tuition average of 3987\$ and the population standard deviation of \$630. Find the 90% confidence interval of the true mean. and B. If a daycare center were starting up and

17. ## Geometry

In a A-frame house, the two congruent sides extend from the ground to form a 34 degree angle at the peak. What angle does each side form with the ground ?

18. ## chemistry

How much NaOH (g) would you need to dissolve in water in order to prepare 2.75 L of a NaOH solution in which [OH-]= 0.50 M?

19. ## Physics

A venturi meter is a device for measuring the speed of a fluid within a pipe. The drawing shows a gas flowing at a speed v2 through a horizontal section of pipe whose cross-sectional area A^2 = 0.0700 m2. The gas has a density of ρ = 1.80 kg/m3. The

20. ## Chemistry..

For the lewis structure of BCl3, does it have a total of 24 valence electrons? Also does it have a total of 4 bonds? If possible can you draw the lewis structure?

21. ## Physics

A monatomic ideal gas expands from 1.00m^3 to 2.50m^3 st a constant pressure of 2.00x10^5 Pa. Find the change in the internal energy of the gas.

22. ## science

what is the heat capacity of iron when a 15.75-g piece of iron absorbs 1086.75 joules of heat energy, and it's temperature changes from 25 degrees celcius to 175 degrees celcius

23. ## statistics

Each of the following is a confidence interval for u = true average(population mean) resonance frequency (Hz) for all tennis rackets of a certain type: (114.4, 115.6) (114.1, 115.9) A) What is the value of the sample mean resonance frequency? B) Both

24. ## statistics

Random samples of size n are selected from a normal population whose standard deviation is know to be 2. Suppose you want 90% of the area under the sampling distribution of x bar to lie within + or - 1 unit of a population mean u. Find the minimum sample

25. ## Economics

5. If the average adult produces \$90,000 of output per year, how much output is lost as a result of adult deaths from secondhand smoke, according to the News on page 74? \$

Tell whether the lines for each pair of equations are parallel, perpendicular, or neither. x + 5y = –20 y = –7/8x – 1 32x – 28y = –36 parallel perpendicular neither I think it's perpendicular - asked this question earlier but didn't get a

27. ## Science

gyazo . com / 2350c4f09d1c4c274e519f9afb639fd4 (USE THE LINK TO ANSWER THESE QUESTIONS. REMOVE THE SPACES TO ENTER INTO THE LINK.) A:What is the genotype of the offspring? B:What is the phenotype of the offspring? C:If two individuals with the same

28. ## statistics

A repeated-measures study uses a sample of n = 20 participants to evaluate the mean differences among three treatment conditions. In the analysis of variance for this study, what is the value for dfbetween treatments?

29. ## statistics

For an experiment involving 2 levels of factor A and 4 levels of factor B with a sample of n = 5 in each treatment condition, what is the value for dfwithin?

30. ## chemistry

a compound is found to be 94.1% o and 5.90% h. its molecular mass is 34.0. what is its molecular formula A. H3O2 B. OH C. H2O D. H2O2 I think D

31. ## stat and research

3. A researcher is interested in whether listening to music helps or hinders test-performance. To control for differences in cognitive level, this researcher decides to use a within-participants design. He selects a random sample of participants and has

32. ## chemistry

Predict how changes effects equilibrium for N2(g) + 3H2(g) -----> 2NH3(g) + heat a. add heat b. remove heat c. add NH3(g) d. remove NH3(g)

Tell whether the lines for each pair of equations are parallel, perpendicular, or neither. y = –1/4x + 10 –2x + 8y = 6 parallel perpendicular neither I think its neither ? please help me understand...

1.An object 2.5cm high is placed 10cm from a converging lens. if the local length of the lens is 5cm, a. How far from the lens will the image be formed? b. How high is the image formed? c. What is the total magnificatio of the object? 2. A terrestrial

35. ## Physics

A block with mass m = 2.00 kg is placed against a spring on a frictionless incline with angle θ=30.0° (see figure). The block is NOT attached to the spring. The spring, with spring constant k = 19.6 N/cm, is compressed 20.0 cm from its unloaded

36. ## statistics

Each of the following is a confidence interval for u = true average(population mean) resonance frequency (Hz) for all tennis rackets of a certain type: (114.4, 115.6) (114.1, 115.9) A) What is the value of the sample mean resonance frequency? B) Both

37. ## Math

Find the most general antiderivative of the function. (Check your answer by differentiation. Use C for the constant of the antiderivative. Remember to use ln |u| where appropriate.) (x^5+x^3+8x)/x^4

Write an equation for the line that is parallel to the given line and passes through the given point. y = 5x + 10; (2, 14) A.y=1/5x +4 B.y=-1/5x-4 C.y=5x-68 D.y=5x+4 I think it might be D...not sure

Tell whether the lines for each pair of equations are parallel, perpendicular, or neither. x + 5y = –20 y = –7/8x – 1 and 32x – 28y = –36 parallel perpendicular neither I think its neither?

40. ## physics

A circular coil (980 turns, radius = 0.078 m) is rotating in a uniform magnetic field. At t = 0 s, the normal to the coil is perpendicular to the magnetic field. At t = 0.027 s, the normal makes an angle of 45o with the field because the coil has made

41. ## Math/statistics

Thirty five percent of adult americans are regular voters. A random sample of 250 adults in a medium size college town were surveyed, and it was found that 110 were regular voters. Estimate the true proportion of regular voters with 90% confidence and

42. ## Science

A solution of silver nitrate is mixed with a solution of potassium sulphide.Write the molecular,total ionic,and net ionic equations illustrating the reaction.

43. ## chemistry

what is the value of [OH-] in a 0.730 M solution of Sr(OH)2?

Tell whether the lines for each pair of equations are parallel, perpendicular, or neither. y = –1/4x + 10 –2x + 8y = 6 parallel perpendicular neither I think its neither ? please help me understand...

45. ## science

you push a friend on a sled your friend and the sled together have a mass of 70 kg if the net force is 33N what is the seld's acceleration?

46. ## chemistry

A 0.682g sample of impure NAHco3 yielded a solid residue consisting of NAc03 and other solid with a mass of 0.467g. What was the mass percent of NAc03 in the sample. The right 85.4% Who help

47. ## maths

A mass of 350 kg is lifted by 2 cables connecting at the same point as shown. Determine the tensions in each cable when the system is in equilibrium.Left hand cable is t1 at 40 degree angle and Right hand cable is t2 at 30 degree angle

48. ## math

a cyclist travels the 30 km from Town A to Town B at an average speed of 25 km/h and immediately continues the journey to town C, which is a further 60 km away at an average speed of 20 km/h. What is the average speed for the whole journey?

49. ## Physics

A 19.5 gram, 56.3 centimeter long steel guitar string is vibrating in its fourth harmonic.  It induces a standing wave in a nearby 48.6 centimeter metal pipe open at one end.  The standing sound wave in the pipe corresponds to the pipe's fundamental

50. ## physics

An object is located 16.8 cm in front of a convex mirror, the image being 11.5 cm behind the mirror. A second object, twice as tall as the first one, is placed in front of the mirror, but at a different location. The image of this second object has the

51. ## maths

The area of 3 adjacent faces of cuboid are x,y and z . If the volume is V , Prove that V^2 = xyz ???

52. ## english-thesis

Heritage plays role x with regard to marriage in Howell’s novel, while in Larsen it plays role y, allowing the man to accept African American women in the former, but reject her in the latter. this was how my teacher edited it but he said something like

53. ## Physics

A sealed can is filled completely with methyl alcohol. Which of these materials could the can be made of so that it would not rupture when the whole system was cooled by 20 degrees Celsius? A.)Aluminum B.)Fused quartz C.)Copper D.)Any of these E.)None of

54. ## Physics

Electromagnetic waves can form standing waves. In a standing wave pattern formed from microwaves, the distance between a node and an adjacent antinode is 0.63 cm. What is the microwave frequency? any help is much appreciated

55. ## Math

Find the effective rate corresponding to the given nominal rate. (Round your answer to the nearest hundredth of a percentage point.) (a) 4%/year, compounded quarterly ? % (b) 3%/year, compounded monthly ? %

56. ## math

Find the present value of \$31,000 due in 4 yr at the given rate of interest. (a) 6%/year, compounded quarterly \$ ? (b) 3%/year, compounded quarterly \$ ?

57. ## college algebra--need help please!!

information is given about a polynomial f(x)whose coefficients are real numbers. Find the remaining zeros of f. degree:5, zeros: -6, 6-i please help and show all work.

58. ## college algebra--need help please!!

information is given about a polynomial f(x)whose coefficients are real numbers. Find the remaining zeros of f. degree:5, zeros: -6, 6-i please help and show all work.

59. ## Chemistry

If the initial volume is 500. ml at a temperature of 30 C, at a constant pressure, what would the new volume be if the temperature was changed to 50 C?

60. ## social studies

Which of the following nineteenth-century inventors is associated with Menlo Park in New Jersey a.Gustavus F. Swift b.Cyrus W. Field c.Alexander Graham Bell d.Thomas Alva Edison

61. ## dps

If a and b are two unit vectors and θ is the angle between them, then a+b is a unit vector if θ is

62. ## Math 8R - Help!!!!!!!!

The expression 2(8a to the 2nd power + a - 1) + 3(a + 3) is equivalent to a) 16a to the 2nd power + 5a + 7 b) 40a to the 2nd power + 10a + 10 c) 10a to the 2nd power + 5a + 7 d) 48a to the 2nd power + 12a + 12 please help!!!!!!!

63. ## STAT

One of the conditions that allows us to use ANOVA safely is that of equal (population) standard deviations. Can we assume that this condition is met in this case? here are options (a) No, since the three sample standard deviations are not all equal. (b)

64. ## statistics

Which of the following is used to calculate the degrees of freedom for the A x B interaction? a. dfbet. treatments – dfA – dfB b. dfA – dfB c. dfwithin – (dfA + dfB) d. dfbet. treatments – dfwithin

65. ## chemistry

what is the percent by mass of carbon in c3h8? A. 18.20% B. 20.0% C. 81.8% D. 85.0% I say A

66. ## Physics

Consider a cube of an unknown material. When heated by 10 K, each side expands by 1%. Using *only this information*, what is the ratio between the coefficent of volume expansion and the coefficient of linear expansion (i.e., beta/alpha)? Express your

67. ## Chemistry

1.a solution that is 6.5×10−2M in potassium propionate C_2 H_5 COOK or KC_3 H_5 O_2 and 8.5×10−2M in propionic acid C_2 H_5 COOH or HC_3 H_5 O_2 what is the ph? 2.a solution that is 8.0×10−2M in trimethylamine, CH_3 _3 N, and 0.10M in

68. ## math

a) 3(x+1)+x+2=2(2x+1)+3 I distributed the equation and got 5=5 as my final answer. b) DON'T UNDERSTAND is the resulting equation from part (a) always true,sometimes ture, or never true? Explain your reasoning.

69. ## Physics

An object is placed 8 cm in front of a convex lens of focal length 6 cm. Find the image location by drawing a ray tracing diagram to scale. Verify your answer using the lens equation.

70. ## college algebra--need help please!!

information is given about a polynomial f(x)whose coefficients are real numbers. Find the remaining zeros of f. degree:5, zeros: -6, 6-i please help and show all work.

71. ## chemistry

A 0.682g sample of impure Na2hco3 yield a solid residue consisting of nahco3 and other solid a mass of 0.467g. What was the mass percent of nac03in sample. I do not understand I want you step by step. Clear explain for me. nahco3 = 84 n22hco3 = 106

72. ## holy heart

Using digits 2, 3, 5, 6, 7 and 9, how many 3-digit numbers can be formed that are divisible by 5 such that the repetition of digits is not allowed?

73. ## chemistry

how many moles are in 243.6 g caco3? A.7.41 mol caco3 B 2.43 mol caco3 C.102.46 mol caco3 D.88.1 mol cao3 I say A

74. ## Math

One side of a rectangle is longer than the other side by 1cm. If the area is 30cm, find its perimeter.

75. ## chemistry

amphetamine (c9h13n) is a powerful stimulant. what is the percent composition of all of the elements in this compound? A. 9%C;13%H;1%N B. 30%C;10%H;60%N C. 60%C;35\$H;5%N D. 80%C;9.6%H;10.4%N I think b

76. ## math

the reciprocal of the expression 2/x + 3/1

77. ## math

each turkey has 2.3 x10 to the 6th power feathers/ How may feathers is that in standard form?

78. ## Chemistry

3C3H8 + 20H2CrO4-->9CO2 + 10 Cr2O3 + 32H2O What mass of chromium (III) oxide will be formed by complete reaction of 1.50g of propane with 35.0ml of 6.26M chromic acid?

79. ## chemistry

What is the concentration of ammonia in a solution if 24.20 mL of a 0.1140 M solution of HCl are needed to titrate a 100.0 mL sample of the solution?

80. ## Biology

What other factors can contribute to the rising in temperatures besides global warming?

81. ## Calculus!

A 16 ft. ladder leans against a wall, with the top being 12 ft. from the wall when time t=0. The top is sliding down at a constant rate of 4 ft./second. Given that the top of the ladder touches the ground at 3 seconds, what is the velocity of the bottom of

use the remainder theorem to find the remainder when f(x) is divided by x-2. then use the factor theorem to divide x-2 is a factor of f(x). f(x)=4x^4-7x^3-5x+2 the remainder is ? is x-2 a remainder of f(x)=4x^4-7x^3-5x+2 please show work

83. ## chemistry

Calculate the amount of solute needed to make each of the solution. 225g of a 10% (m/m) K2CO3 solution .50kg of a 18% (m/m) KOH solution please show work thanks

84. ## dpis

The rate of change of radius of a spherical air bubble is 0.002 cm/s. What is the rate of change of its surface area when its radius is 2 cm?

5t-10t^2÷5t

5t-10t^2÷5t

87. ## STAT

One of the conditions that allows us to use ANOVA safely is that of equal (population) standard deviations. Can we assume that this condition is met in this case? here are options (a) No, since the three sample standard deviations are not all equal. (b)

88. ## Math 8R - Help!!!!!!!!

If one-third of a number is 6 less than haft of the number, what is the number? a) 30 b) 12 c) 18 d) 36

89. ## Chemestry

Find the molarity of a solution containing 0.75 mol of NaCl with a volume of 1.5 L.

90. ## Math - help please

Write the equation of a line that is perpendicular to the given line and that passes through the given point. y – 3 = (x + 2); (–2, 3) A. Y+3= -3/8(X-2) B.Y-3=-3/8(X+2) C.Y-2=-3/8(X+3) D. Y+3=3/8(X-2) I am not sure how to do this problem...please

91. ## math

How high is a wall that casts a 15ft shadow at the same time that a 4ft flag pole casts a 4ft shadow?

92. ## math

what is the difference btwn 5^3 and (5)^3? When ever they have a question in which they have a a number squared and then they have another question right after it asking the difference between the same question in parenthesis..is it a trick question? is

93. ## Physics

In an interference of light experiment, coherent light that contains two wavelengths: 640 nm (red-orange) and 425 nm (indigo-blue), passes through two narrow slits separated by 5.35 Î¼m, and the interference pattern is observed on an observation screen

94. ## Adult Fevelopment and life Assessment

Why is it importasnt for a university to maintan hgh standards when it comes to academic integrity.

95. ## Chemistry

what is the name of the ions that are formed when the following compounds dissolve in water. (a) BaBr2 (b) (NH4)2CrO4 (c)HBr

96. ## Algebra 2 ..

what is the difference between -16^1/4 and (-16)^1/4

97. ## math

if 3 bananas cost £1.14 how much will 5 of them cost? and how do ypu work it out?

98. ## math

if 3 bananas cost £1.14 how much will 5 of them cost? and how do ypu work it out?

99. ## AP World History

Describe the complexities of trade in Post-Classical world and compare to today.

100. ## social studies

If you were a reform-minded person who, above all, loathed the social problems associated with alcohol, you would have been especially sympathetic to the

101. ## college algebra--need help please!!

use the intermediate value theorem to show that the polynomial function has a zero in the given interval. f(x)=x^5-x^4+9x^3-5x^2-16x+5;[1.3,1.6] f(x)1.3= ? simplify answer f(x)1.6= ? "

102. ## health

if rheumatoid factor 1gM under ELISA process shows around 320.6 RU/mL and thyroid stimulating hormone TSH at 13.37 and ESR at 60mm/hour ra factor : non reactive 1:2 anti nuclear anti bodies ANA 0.39 (n) pl tell me what would happen to the patient and what

103. ## calculus II

Suppose R is the region in the plane enclosed by y = x2 and y = 4. a) Compute the perimeter P and area A of R, and then compute the ratio Q = A/P2. Note By squaring the perimeter the ratio becomes independent of the units chosen to measure the region. b)

104. ## college algebra--need help please!!

solve the equation in the real number system. 2x^4-23x^3+75x^2-88x+28=0 What are the real solutions of the equations? please show work. I do not know how to work this at all

105. ## college algebra

solve the inequality algebraically 11x-3 is greater than or equal to - 4x^2

106. ## STAT

One of the conditions that allows us to use ANOVA safely is that of equal (population) standard deviations. Can we assume that this condition is met in this case? here are options (a) No, since the three sample standard deviations are not all equal. (b)

107. ## Physics

An engine does 15kJ of work while rejecting 37 kJ to the cold reservoir. What is the efficiency of the engine?

108. ## Physics

In order for a satellite in free fall to maintain uniform circular motion, ______________. a) there must be a tangential acceleration b) there must be angular acceleration c)there must be a centripetal force d) there must be a circumventing force Its

109. ## math - Ms. Sue

What is the slope of the line that passes through the pair of points? (-5/3, -1)and (-2, 9/2) A.2/33 B.-2/33 C.-33/2 D.33/2 I think it is D?

110. ## english

I need to write a short story with the ending relating to "That is how I became Captain"

Tell whether the lines for each pair of equations are parallel, perpendicular, or neither. y = –x + 10 and –2x + 8y = 6 parallel perpendicular neither I think its neither again

112. ## social studies

A ruler should lead by_____? 8 letter word

113. ## hum 101

What are some examples of a situation that the strateigies used in "The Art of The War by Sun Tzu be applied to?

114. ## Maths

Factorise X^2 - y^2 - 2x + 2y

115. ## math

the reciprocal of the expression 2/x + 3/1

116. ## statistics

Random samples of size n=10 are taken from a normal population whose statndard deviation is known to be 5. Calculate the area under the sampling distribution curve for x bar between the points u-1 and u+1. That is find the probability that the sample mean

118. ## health

what is the cause and effect of mouth ulcers and sores in elderly clients

119. ## health

what is the cause and effect of tooth decayin elderly client

120. ## Agriculture

Why is there difference in the quality of the poultry products?

121. ## physics

a 10 kg weight is on an inclined plane. 10 ft long and 6 ft high. if there is no friction, what force parallel to the plane will prevent the body from slidin?

122. ## chemistry

Which material would you expect to have a greater bandgap energy between indium nitride (InN) and indium phosphide (InP)?

123. ## algebra

Which equation is the equation of a line that passes through (-10,3) and is perpendicular to y=5x-7?

124. ## sant singh sukha singh school

The mapping is f:N →N, given by F(n)= 2n^3=1,n belongs to N. A. one-one and onto B. onto not one-one C. one-one not onto D. neither one-one nor onto

125. ## math

if 3 bananas cost £1.14 how much will 5 of them cost? and how do ypu work it out?

126. ## English and Grammar

first draft of my report and i need help in improving this. i didn't made up all the information here all comes from a book. Dissociative identity disorder is defined in the DSM-IV-TR as the presence of two or more personality identities that repeatedly

127. ## English and Grammar

I choose to do research on Avoidant personality disorder or APD because a friend of is suffering from APD and I’m having trouble how to approach him. My friend’s name is Jim. He told me that he started to feel the symptoms when he was in his teen age

128. ## Geo

How many ecozones are there in canada??????/

129. ## algebra

i need help with -0.39 is greater or less to -0.31