# robin

Popular questions and responses by robin
1. ## Chemistry

Explain why the solubility of PbF2 is pH dependent, but the solubility of PbCl2 is not. I know the solubility of PbF2 is pH dependent because the solubility would increase as the solution becomes more acidic because the F^- ion is the conjugate weak base

2. ## Algebra

Form a third degree polynomial function with real coefficients such that -7 + i and -9 are zeros

3. ## Physics

Some insects can walk below a thin rod (such as a twig) by hanging from it. Suppose that such an insect has mass m and hangs from a horizontal rod as shown in the figure, with angle θ = 37°. Its six legs are all under the same tension, and the leg

4. ## Statistics

A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. Assuming a standard deviation of 3 hours, what is the required sample size if the error should be

-2I3mI+3

6. ## math

how to find slope and graph y+3=1/2(x+2)

7. ## Calculus

A rancher wants to make a rectangular pen to house her animals. She will divide it up with 3 fences down the middle parallel to one side. If she has 14000 ft of fencing to work with, what are the dimensions of the pen of greatest area? Width = Length =

8. ## math

write the phrase as an expression... 7 more than the quotient of a number y and 5

9. ## Calculus

Gravel is being dumped from a conveyor belt at a rate of 10 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always equal. How fast is the height of the pile increasing when the pile is 16 feet

If the wavelength of line B is 142.5 nm, calculate the wavelength of line A. Line A is the transition of n=6 to n=3 Line B is the transition of n=5 to n=3

11. ## College Algrebra

Joel can run around a 1/4 mi track in 66 sec. Jason can run around the track in 60 sec.If the runners start at the same point on the track and run in opposite directions, how long will it take the runners to cover 1/4 mile?

12. ## physics

a geosynchronous satellite orbits at a distance from earth's center of about 6.6 earth radii and takes 24 h to go around once. what distance in meters does the satellite travel in one day? what is its orbital velocity in m /s?

13. ## math

a color printer prints 28 pages in 12 minutes. How many pages does it print per minute

14. ## English 2

Water that aids digestion is really true.Identify the function of the noun clause.

15. ## Physics

A roller coaster has a mass of 425 kg. It sits at the top of a hill with height 66 m. If it drops from this hill, how fast is it going when it reaches the bottom? (Assume there is no air resistance or friction.)

16. ## Geology

There is also a graph i can't move it. Building Isochrons and Determining the Ages of Three Rocks Page 15 of 17 For each of the three rocks listed below follow these steps to determine the rock's age of formation. 1. Prepare an isochron by plotting the

17. ## math

Matthew used 1/5 of a box of flour for cooking and 3/4 of the remainder to make bread. The rest of the flour was packed equally into 5 containers. What fraction of the total amount of flour was in each container?

18. ## Calculus

Find the point on the line 7x+5y−2=0 which is closest to the point (−6,−2).

19. ## Calculus

A cable hangs between two poles of equal height and 40 feet apart. At a point on the ground directly under the cable and x feet from the point on the ground halfway between the poles the height of the cable in feet is h(x)=10+(0.4)(x^1.5). The cable weighs

20. ## math

3 pumps, working 6 hours a day, can empy a water tank in 2 days. How many hours a day must 9 pumps work to empty the same tank in 1 day?

21. ## math

A gallon jug of milk is 3/4 full. After breakfast the jug is 1/12 full. Find the difference of the amounts before breakfast and after breakfast.

22. ## Calculus

According to the National Health Survey, the heights of adult males in the United States are normally distributed with mean 69.0 inches and standard deviation 2.8 inches. A. What is the probability that an adult male chosen at random is between 61 inches

23. ## Calculus

Evaluate the integral below by interpreting it in terms of areas. In other words, draw a picture of the region the integral represents, and find the area using geometry. ç6 −6 36−x^2dx

24. ## Physics true false

true false The speed of a particle is always positive. True False The average speed of a particle is equal to the magnitude of its average velocity. True False The acceleration of a particle can be non-zero when its speed is constant. True False When the

25. ## physics

a geosynchronous satellite orbits at a distance from earth's center of about 6.6 earth radii and takes 24 h to go around once. what distance in meters does the satellite travel in one day? what is its orbital velocity in m /s?

26. ## Database design

How can you conduct evaluation and revision within the SDLC and DBLC frameworks? Maybe try here: http://www.google.com/search?hl=en&lr=&as_qdr=all&q=SDLC++DBLC+frameworks+evaluation+evaluate Thanks Lance but I do not find what I need there, or if it is I

27. ## Chemistry

Adding 1.00 g of benzene, C6H6, to 80 g of cyclohexane, C6H12, lowers the freezing point of the cyclohexane from 6.5 to 3.3 degree celsius. What is the value of kf for cyclohexane?

28. ## Calculus

Two cars start moving from the same point. One travels south at 60 mph and the other travels west at 25 mph. At what rate is the distance between the cars increasing 2 hours later? Let x = the distance covered by the south traveling car. Let y = the

29. ## math

R. H. Bruskin Associates Market Research found that 30% of Americans do not think that having a college education is important to succeed in the business world. If a random sample of five Americans is s selected, find these probabilities. (a) Exactly two

30. ## Enlgish, possessive form of singular and plural no

possessive form of family, brother, suitcase, child, government, pen, train, tree, woman, refugg, families, brothers, suitcases, children, governments, pens, trains, trees, women,refugees

31. ## psychology

Identify intervention strategies to deal with burnout

32. ## Chemistry AP

what does this mean (we are on quantum) The figure below represents part of the emission spectrum for a one-electron ion in the gas phase. All the lines result from electronic transmissions from excited states to the n = 3 state. the graph is like this A B

33. ## math

A car averaged 48 miles per hour traveling 672 miles from Washington to Orlando. How long was the trip?

34. ## math

s+1/4=4/8 solve the proportion

35. ## math

Jay spent 6 hours playing games, studying and talking with his friends. he spent 2/5 of the time playing games and 1/2 of the time studying. how many minutes did he spend talking with his friends?

36. ## math

In the continental United States, the ratio of states that border an ocean to states that do not border an ocean is 7 : 9. How many of the states border an ocean?

37. ## math

you spend \$16 on 3 notebooks and x binders. Notebooks cost \$2 each and binders cost \$5 each. Write an equation you can use to find the number of binders you bought.

38. ## Algebra

In a large city, taxicabs charge \$4.00 for the first one-fifth mile and 0.38 for each additional one- fifth mile. Frank has only \$8.50. What is the maximum distance he can travel?

39. ## algebra

how do you simplify (sqrt18)over(sqrt8)-3? And (4-3sqrt2)squared? I tried but get some unreal answer. thanks in advance.

40. ## MATH

Create a graph of a function given the following information: The instantaneous rate of change at x = 2 is zero. The instantaneous rate of change at x = 3 is negative. The average rate of change on the interval 0

41. ## Calculus

Find the absolute maximum and the absolute minimum values of f(x)=x−7cos(x) on the interval [−ð,ð).

42. ## Math

Rearrange this expression into quadratic form, ax2 bx c = 0 0.20= ((x^2)/(55-x)) where a = 1, and identify the values of b and c.

43. ## chemistry

The vapor pressure of water @ 80 degrees C is 0.467 atm. Find value of Kc for the reaction H2O(l) to H2O(g) @ this temp.

44. ## PHYSICS ---HELP!

A man doing push-ups pauses. His mass is 80-kg. Determine the normal force exerted by the floor on each hand and on each foot. a = 40 cm b = 95 cm c = 30 cm W = mg = 784 N

45. ## math

PV=nRT solve for T

46. ## math

1/4(n-6)=1/4n-3/2

47. ## math

you buy a ring box as a birthday gift that is in the shape of a triangular prism. What is the least amount of wrapping paper needed to wrap the box? The lengths of the box are 14.5 cm, 8 cm, 10 cm, 10.5 cm

48. ## math

The ratio of the side lengths of a triangle is 2 : 3 : 4. The shortest side is 15 inches. What is the perimeter?

49. ## math

6 1/2 - 7/8 divided by 5 11/16

50. ## math

you are creating identical candy bags using 18 chocolate bars and 30 peanut butter cups. What is the greatest number of bags you can fill using all the candy

51. ## math

Your bedroom is in the shape of a square that is 12 feet long on each side. Will a circular rug with a circumference of 40.82 feet fit into your room? If not, by how many feet is the rug too wide?

52. ## math

on a 10 question quiz you correctly answer four one point questions and five two point questions. you earn 87.5% of the possible points on the quiz. a. how many possible points is the quiz worth b. how many questions did you miss c. how many points was

1/8+6/7+1/6=

54. ## math

Two vertices of a triangle are F (1, −4) and G(6, −4). List two possible coordinates of the third vertex so that the triangle has an area of 20 square units.

55. ## math

jill has 8 yards of cloth. she wants to cut it into pieces that are 1/4 yard long. How many pieces can she cut from the length of cloth

y/9=44/54

57. ## Math

Is -n always, sometimes, or never a positive number? Explain. I don't know what they mean by -n - is a negative number?

58. ## math

Bass: The bass in Clear Lake have weights that are normally distributed with a mean of 2.3 pounds and a standard deviation of 0.6 pounds. (a) If you catch one random bass from Clear Lake, find the probability that it weighs less than 1 pound? Round your

Given m

60. ## Statistics

Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the binomial probability formula to find the probability of x successes given the probability of success on a single trial, n=9, x=2, p=0.35.

61. ## albebra

solve arithmetically and algebraically. The perimeter of a rectangle is 54 cm. Its length is 6 cm. What is its width?

Prepare a one-page description of your plans to solve the problem for one of the following research studies. Use the following headings for the problem:

63. ## Physics

For the vectors with a = 3.3 and b = 2.2, what are (a) the z component of AxB, (b) the z component of AxC, and (c) the z component of BxC?

64. ## Physics

In the sum A+B=C, vector A has a magnitude of 10.2 m and is angled 48.0° counterclockwise from the +x direction, and vector C has a magnitude of 15.0 m and is angled 22.0° counterclockwise from the -x direction. What are (a) the magnitude and (b) the

65. ## Physics

A particle starts from the origin at t = 0 and moves along the positive x axis. A graph of the velocity of the particle as a function of the time is shown in the figure; the v-axis scale is set by vs = 7.0 m/s. (a) What is the coordinate of the particle at

66. ## Calculus

How can I get partial sums of a series on a TI 89 calculator?

67. ## Calculus

Calculate 20 terms for the sequence P0=-.5 and k=1.8, P0=.5 and k=2.8, and P0=.3 and k=1.8. Does the limit depend on the choice of P0? Does it depend on the choice of k?

68. ## Calculus

Solve the separable differential equation 10x−6ysqrt(x^2+1)dy/dx=0. with the initial condition y(0)=4.

VOCABULAY/CONTEXT CLUES WHAT DOES COMBUSTION MEAN? wHAT CLUES HELP YOU TO DETERMINE THE MEANING? wHAT IS A WAFT? WHAT CLUES HELP YOU TO DETERMINE THE MEANING? HOW DOE CONTEXT CLUES HELP YOU DTERFMINE THE MEANING OF DINGY?

70. ## Calculus

A) Find the average value of f(x)=x^3-x+1 on the interval (0,2) B) Find c so that f(c)equals the average value

71. ## statistics

a sample of 50 women is obtained and their heights (in inches) and pulse rates (in beats per min) are measured. the linear correlation coefficient is 0.229 and the equation of the regression line y= 17.9 +0.870x where x represents hight. the mean of the 50

72. ## Calculus

Determine whether the integral is divergent or convergent. If it is convergent, evaluate it. If it diverges to infinity, state your answer as INF. If it diverges to negative infinity, state your answer as MINF. If it diverges without being infinity or

Evaluate the integral (3x^2-16x-19)/(x^3-4x^2-3x+18)

74. ## Calculus

Snow is falling vertically at a constant rate of 8.0 m/s. At what angle from the vertical do the snowflakes appear to be falling as viewed by the driver of a car traveling on a straight, level road with a speed of 50k.h?

75. ## MATH

f(x)=3x+2 g(x)=-2x+1 a) Write an equation for ( f+ g)(x) b) Determine (f+g)(6) c) Determine (fg)(6) d) Determine the domain of (f/g)(x)

76. ## Calculus

The motion of a spring that is subject to dampening (such as a car's shock absorber)is often modeled by the product of an exponential function and a sine or cosine function. Suppose the equation of motion for a point on such a spring is

77. ## Chemistry

two solutions are prepared using the same solute solution a: 0.27g of the solute disolves in 27.4g of t-butanol solution b: 0.23g of the solute disolves in 24.8g of cyclohexane which solution has the greatest freesing point change? show calculations and

78. ## english, possessive nouns

Directions: Wrie each sentence. Change the underlined phrase to show possession. The honesty of children is refreshing. The honesty of children is the underline part of the phrase.

79. ## Algebra

69% of the students at a school are involved in after-school activities. There are 598 students in the school. Which is the best estimate of the number of students in after school activities? A. 360 B. 380 C. 420 D. 450

80. ## science

When water is split into hydrogen and oxygen what happens- is it a change in matter

81. ## math

During a sale at the local department store, you buy three sweatshirts and two pairs of sweatpants for \$85.50. Later you buy three more sweatshirts and four more pairs of sweatpants for \$123.00 What is the sale price of each sweatshirt and each pair of

82. ## Physics

A hockey puck is sliding on frictionless ice. It slams against a wall and bounces back toward the player with the same speed that it had before hitting the wall. Does the velocity of the hockey puck change in this process?

83. ## com 155

• Write several sentences describing a recent interaction with a friend or family member about personal finance or credit cards. This interaction may be imagined or real. • Use at least five different pronouns in your sentences. • Identify all

84. ## Psychology

what is an example of "case study method" psychology?

85. ## physics

A man doing push-ups pauses in the position shown in the figure . His mass m = 80 kg. In push up position: From hands to waist = 40 cm From waist to feet = 95 cm height - heel of foot to ground = 30 cm Determine the normal force exerted by the floor on

86. ## Mat 116

Solve the system by graphing 8x-6=-18 6y-8x=18 divide 1 equation by 2 4x-3y=-9 divide 2 equation by -2 -4x-3y=-9 this makes both equation dependent slope intercept of two equation 4x-3y=-9 3y=4x+9 this makes this consistent. Just helping if I can.

87. ## math

the second angle of the a triangle is twice as large as the first angle. the measure of the third angle is 20 degrees less than the second. how large is each angle?

88. ## chemistry

How do it geth the equation for 50.0 grams of iron(II)carbonate react completely with hydrochloric acid how many grams of carbon dioxide gas may be produced?

essay on should students only have to take reading andmath to go to 9th grade agree or disagree?

90. ## Grammar

My teacher edited my story and I do not understand the abbreviations that she used. Does anyone know what she means by SV and SA.

91. ## math

A calcium ion has 20 protons and 18 electrons. Each proton has a +1 charge and each electron has a -1 charge. What is the charge of the calcium ion?

92. ## math

How long will it take a bird traveling at an average speed of 12 miles per hour to travel 202 miles while flying south for winter?

93. ## math

A cheetah traveling at 31 m/s chased its prey for 11 seconds. What distance did the cheetah travel during the chase?

94. ## math

Light travels at 186,000 miles per second. Light takes about 11⁄3 seconds to travel from the earth to the moon. Calculate the distance between the earth and the moon based on the speed of light.

95. ## math

You are having a lemonade stand and the ingredients to make lemonade comes out to about \$.08 per cup. If you sell each cup for \$.75 by what percentage did you markup a cup of lemonade?

3(x+4)>12

97. ## math

Shawntelle is solving a problem involving a triangular pyramid. You hear her say that "bee" is equal to 24 inches. How can you tell if she is talking about the base area B of the pyramid o about the base b of the triangle?

98. ## math

Steve picks 55 pounds of pears. He packs an equal amount of pears into 6 bags. He then has 4 pounds of pears left. What is the weight of pears in each bag?

99. ## math

write the ratio as a fraction in simplest form 5/4 to 2/3