# Darren

Newest questions and responses by Darren
1. ## math

The dilation D: (x, y) → (0.2x, 0.2y) has been applied to the polygon S(–5, 5), T(–5, 10), U(5, 15). What are the coordinates of the image points? a S'(–1, 1), T'(–1, 2), U'(1, 3) b S'(–4.8, 5.2), T'(–4.8, 10.2), U'(5.2, 15.2) c S'(–5.2,

2. ## Maths

A square prism and square pyramid have the same base and the same surface area. Show that the slant height, l, of the pyramid is l=5/2 x s where s is the length of the base.

3. ## algebra

5:11 and 6:12 7:13 and 21:39 8:14 and 24:30 10:20 and 20:30 which pair of ratios form a proportion?

4. ## math

A step ladder 2.2m high was opened making an angle of 30° Calculate distance between legs of ladder

5. ## chemistry

If 10.0 L of butane and oxygen are combined at the same temperature and pressure, which gas will be left over after reaction? Include your calculation/reasoning.

7. ## Chemistry, pH

What is the (OH-) when pH = 4.25

8. ## Calculus

Hi. I need help with finding the derivative of the function: y= [(sec^7 x)/7] - [(sec^5 x)/5] Thanks!

9. ## Calculus

Hi! I need help finding the derivative of this function. f(x)= ln [(x(x-1))/(x-2)] Thank you.

10. ## Math

Given the following prime factors, determine the original number as well as all of its factors. 2*3*5*7 I know that 2*3*5*7 is 210 but I don't know what to do next.

11. ## Psychology

Indicate the independent variable and dependent variable: A research psychologist, working in a federal prison, is asked to assess the effectiveness of a new life skills program in promoting problem-solving skills. From a pool of 70 inmate volunteers, the

12. ## Geometry

A diver is currently at the surface of the water out at sea. If he descends into the ocean at an angle of depression of 32 degrees, what will be his depth to the nearest tenth of a foot after swimming for 5 minutes

13. ## Physics

Physics Help!!!!! Maximum Kinetic Energy based on a graph? A 2.50kg ball is attached to an unknown spring and allowed to oscillate. The figure shows a graph of the ball’s position x as a function of time t.(Figure 1) Part A: What is the maximum kinetic

14. ## statistics

Given that the general population is normally distributed on a standard scale measuring math aptitude with Mean = 50 (s.d. = 10), approximately what percentage of the population has a math aptitude score between 40 and 60?

15. ## Calc

Find the area between the x axis and the graph of y = (2e^x)/(1+e^(2x)) a. e^2 b. pi c. pi/2 d. 2pi d. none of the above

16. ## Calc

Calculate the area under the curve y=e^-x above the x axis on the interval [1, infinity). a. infinity b. 0 c. -1/e d. 1/e e. none of the above

17. ## Calc

Evaluate the integral or show that it diverges: Integrand 0, lower, to 3, upper, (1/x)dx. a. infinity b. negative infinity c. 0 d. ln 3 e. none of the above

18. ## Calc

Find the limit as x approaches 0: (e^x^2-1)/(2x^2) a. 0 b. 1/2 c. infinity d. does not exist e. none of the above

19. ## Calc

Evaluate the integral (3x+4)/[(x^2+4)(3-x)]dx a. (1/2)ln(x^2+4) + ln|3-x| + C b. (1/2)arctan(x/2) + ln|3-x| + C c. (1/2)arctan(x/2) - ln|3-x| + C d. ln|(sqrt(x^2+4)/(3-x))| + C e. None of the above

20. ## Calc

Compute the average value of f(x) = x/(x+3) over the interval [-a,a], 0 < a < 3. a. 1 + (3/2a)ln[(3-a)/(3+a)] b. 2a + 3ln[(3-a)/(3+a)] c. 3/(9-a^2) d. 1/(2a) e. None of the above

21. ## Math

93*3^2-6^2-4^3

22. ## math

the gift box fits 2 layers of 10 cubic inches. what is the volume of the box.

23. ## Physics

Calculate a space shuttle territory 250 km above Earth's surface. Earth's mass is 6.0 * 10^24kg and its radius is 6.38 * 10^6 m (6380km)

24. ## Physics

A 1800-kg car experiences a combined force of air resistance and friction that has the same magnitude whether the car goes up or down a hill at 28 m/s. Going up a hill, the car's engine produces 52 hp more power to sustain the constant velocity than it

25. ## Math

An external sinusoidal force is applied to an oscillating system which can be modelled by a model spring and a damper. The general solution of the equation of the motion is given by, x = 5 + 3.071cos(2πt – β) + 3.14exp(-7.96t) cos(αt + φ) where α,

26. ## Math

A particle A of mass 2.11 kg collides with another particle B of mass 3.86 kg. Their initial velocities are u1 = 2.16i + 0.88j and u2 = 0.7i + 1.12j just before impact. After collision, they both merged and becomes a composite particle, which travel with a

27. ## Algebra 2

(x^3+8) x ((x-2)/(x^2-2x+4))/ (x^2-4)/(x-6)

28. ## Statistics

The average age of vehicles registered in the united states is 96 months, with a standard deviation of 16 months. If a random sample of 36 vehicles is selected, find the probability that the mean of their ages is between 90 and 100 months. Provide four

29. ## chemistry

The purity of a pharmaceutical preparation of sulfanilamide, C6H4N2O2S, can be determined by oxidizing the sulfur to SO2 and bubbling the SO2 through H2O2 to produce H2SO4. The acid is then titrated with standard NaOH. Calculate the purity (%w/w

30. ## chemistry

A 0.4515 g sample of pure CaCO3 was transferred to a 500 mL volumetric flask and dissolved using 6M HCl then diluted to volume. A 50.00 mL aliquot was transferred to a 250mL Erlenmeyer flask and the pH adjusted. Calmagite was used as an indicator the

31. ## chemistry

The amount of Fe in a 2.0008 g sample of an iron ore was determined by a redox titration with K2Cr2O7. The sample was dissolved in HCl and the iron brought to a +2 oxidation state. Titration required 26.48 mL of 0.034 M K2Cr2O7. Calculate the iron content

32. ## GPA help

if i had a 1.875 and i get a C to go up to a B what is my GPA? will it be a 2.0? i need help i want to play baseball.

33. ## English

if i had a 1.875 and i get a C to go up to a B what is my GPA?

34. ## French

Can someone please help edit my French? My French: Quelles matières étudiez-vous cette année ? Moi, je fais deux les maths, la chimie, la physique, l’anglais et le français. Je n’aime pas les maths parce que il y a beaucoup des devoirs pour les

35. ## Algebra 2

You are designing a kit for making sand castles. You want one of the molds to be a cone that will hold 48π cubic inches of sand. What should the dimensions of the cone be if you want the height to be 5 inches more than the radius of the base?

24+1+1/8

37. ## chem

What volume of a 8.50M Na2CO3 solution would be required to prepare 220.00mL of a 8.20%w/v Na2CO3 solution?

38. ## chem

mix 35.50 mL of a 0.201 M solution of K2CrO4 with 35.50 mL of a 0.201 M solution of AgNO3, what mass of solid will form?

A 40.6-kg crate rests on a horizontal floor, and a 69.1-kg person is standing on the crate. Determine the magnitude of the normal force that (a) the floor exerts on the crate and (b) the crate exerts on the person.

40. ## physics

In a European country a bathroom scale displays its reading in kilograms. When a man stands on this scale, it reads 90.4 kg. When he pulls down on a chin-up bar installed over the scale, the reading decreases to 79.5 kg. What is the magnitude of the force

41. ## phsyics

A 40.6-kg crate rests on a horizontal floor, and a 69.1-kg person is standing on the crate. Determine the magnitude of the normal force that (a) the floor exerts on the crate and (b) the crate exerts on the person.

42. ## physics

In a European country a bathroom scale displays its reading in kilograms. When a man stands on this scale, it reads 90.4 kg. When he pulls down on a chin-up bar installed over the scale, the reading decreases to 79.5 kg. What is the magnitude of the force

43. ## physics,

A student presses a book between his hands The forces that he exerts on the front and back covers of the book are perpendicular to the book and are horizontal. The book weighs 30.8 N. The coefficient of static friction between his hands and the book is

44. ## Phsyics

A 40.6-kg crate rests on a horizontal floor, and a 69.1-kg person is standing on the crate. Determine the magnitude of the normal force that (a) the floor exerts on the crate and (b) the crate exerts on the person.

45. ## Math- Pre calculus

A community bird-watching society makes and sells simple bird feeders to raise money for its conservation activities. The materials for each feeder cost \$5, and the society sells an average of 20 per week at a price of \$9 each. The society has been

46. ## algebra

The product of two consecutive positive even numbers is 840. What are the numbers? (Enter solutions from smallest to largest.)

47. ## Math

Solve the equation. (Enter solutions from smallest to largest. If there is no solution, enter NONE in the answer boxes.) 4x^2 = 7x + 2

48. ## Physics

You are holding a 5 kg dumbbell straight out at arm's length. Assuming your arm is 0.63 m long, what torque is the dumbbell exerting on your shoulder?

49. ## math

I'm having trouble solving this problem: definite integral (2-t)(sqrt(t)), 0..2

50. ## Math

What property changed(4c + 3c) + 6 to (4+3)c + 6?

51. ## pre- algebra

Solve for m. -6m - 7 = -5m + 3

52. ## Physics

Suppose you wish to visit a star which is 450 light years away, and that you want your 21000 kg rocket to move so fast that you only age 20 years during the round trip. a. How fast must the rocket travel relative to the Earth? Give your answer as the

53. ## Physics

a)What speed must one frame of reference be moving relative to another for the two to disagree about the length by 1% b)What speed must one frame of reference be moving relative to another for the two frames to disagree about time intervals by 1%? Both

54. ## Physics

At what speed must one frame of reference be moving relative to another for the two frames to disagree about lengths by 1%? Express your result as a fraction of the speed of light. At what speed must one frame of reference be moving relative to another for

55. ## Physics

A rocket cruising past Earth at 0.79c shoots two bullets at 0.92c relative to the rocket with one of the bullets fired along the direction of the rocket's motion and the other fired opposite the rocket's motion. (a) What velocity does an Earth-based

56. ## Math

An airplane takes off in a straight path. When it has traveled 5 km, it is 3 km high. To the nearest kilometer, what is the horizontal distance, d that the airplane has flown over?

57. ## chemistry

A 0.040M solution of a weak acid has a pH of 3.02 at 25°C . What is the value of Ka for the acid?

58. ## chemistry

What are the concentrations of H3O+ and OH- and what is the pH of a 0.15 M solution of Na2CO3 (at 25 °C).

59. ## accounting

I'm stumped in reference to figuring the answer for the following question. If anyone can help I would be so thankful. The question is as follows: A county fire department receives property tax revenue on a 55% (December), 40% (April), 5% (June) basis. The

60. ## Media Studies

Hi there, I need to make a response to this quote, could anyone give me ideas of what this quote might mean in relation to media today. "The Internet is to News, What Car Horns are to Music" Thanks.

61. ## health

When HIPAA requires auhtorization to disclose information the authorization must

62. ## Englsih, Sonnets

Can someone help me with Sidney Sonnet 31 and 39 questions? The sonnets are at the bottom if you need them. 1. The unifying theme of Sidney's Sonnets 31 and 39 is... a. natural beauty b. hopeless love c. relief from pain d. endless suffering 2. Which of

63. ## algebra

A person bought 17 gifts for his nieces and nephews. The gifts were dolls for the nieces at \$12.99 each, and robots for the nephews at \$10.99 each. The total spent was \$198.83. How many of each gift was bought?

scientist needs 5L of 12% solution. She has on 10% and 17% solution. How much of each does

65. ## Vectors

Could someone help me solve these system using elementary operations, I am having trouble with both of them. x+y+z =0 x-y =1 y-z =-5 (For the one above the answer is (-1,-2,3) 2x-y =0 2y-z =7 2z-x =0 (For the one above the answer is (2,4,1)

66. ## Vectors

Could you please help me solve this question: Solve this system of equations using elementary operations. 1. x/3 + y/4 + z/5 =14 2. x/4 + y/5 + z/3 =-21 3. x/5 + y/3 + z/4 =7 So far, I have multiplied all three equations by 60, to turn them into whole

67. ## Biology

Why is there electrical activity in the brain? Describe how it is used by neurons.

68. ## English

Hi there, I am doing a presentation comparing women in Hamlet times to women today. But i need help finding a cartoon representing women from Hamlet's time. Please direct me to links for this.

69. ## Vectors

A mass 0f 10kg is suspended by 2 pieces of string, 30 cm and 40 cm long, from twp points that are 50cm apart and at the same level. Find the tension in each piece of string.

70. ## neighborhood know how!

all neigh have rights.with these rights come responsibilities.draw a picture of a responsible neighbor.

71. ## bsa 375

Why is a systems development process needed? What is the objective of each phase of the SDLC? Describe briefly? How important are feasibility studies. The text mentions four types of feasibility studies: operational, technical, economic, and schedule. In

72. ## cummunity helper project

my cummunity helper is a

73. ## Social Studies

what would happen if wheat was no longer a resource to the U.S.

74. ## out of curiosity...

does anyone know what is the pathway used to board an airplane? the bridge-like pathway that connects to the doors of the plane and are used to board and go off the plane? answer would be greatly appreciated..tnx :)

75. ## Intro to Accounting

Les Fleurs, a boutique in Paris, France, had the following accounts in its accounting records at December 31, 20X2 (amounts in Euros, denoted as "E") Purchases………………... E250,000 Freight In……………… E8,000 Sales discounts………….

76. ## diction

what is the opposite of cohesive but still using cohesive in it incohesive?

77. ## Naming

what are people from rhode island called? rhode islanders?

78. ## writing

PRONOUN REFERENCES. EMPLOYEES ARE BEGINING TO TAKE ADVANTAGE OF THE COMPANY'S ATHLETIC FACILITIES. THEY OFFER SQUASH AND TENNIS COURTS, A SMALL TRACK, AND SERVERAL TRAMPOLINES.

79. ## math

solve for x. 1.25x^2=13 2.2(x-5)^2=3

81. ## science

Scientists debate about the use of fossils as a tool to determine records of various events, such as the vanishing of the dinosaurs or the origin of our ancestors.discuss the role of fossils in helping scientists develop accurate records of the geologic

82. ## algebra

I don't know how to find the GCF if the variables are different. For example, 48a^3 and 16b^5.

83. ## math right triangle

the hypotenuse of a right triangle is 1 inch longer than one leg and 8 inches longer than the other. Find the length of each side of the triangle. Let l1, l2 be the legs. l1^2 + l2^2 = h^2 but h= l1+1 and h= l2 + 8 solve these for l1, l2, put them in the

1. ## Chemistry

I don't know lot but you have done right well-done I am doing PhD in chemistry

posted on November 21, 2017
2. ## Accounting

These were the present values I had obtained. 1. PV = 1,180,000 2. PV = 671476 3. PV = 1,087,033 4. PV = 1,204,627 4 is the one I had trusted myself least on.

posted on April 26, 2017
3. ## Higher Chem

16.11008228

posted on January 18, 2017
4. ## math

dontknow

posted on January 3, 2016
5. ## math

posted on October 14, 2015
6. ## Chemistry, pH

im confused, is the answer 1.77827941x10^-10 or 5623413252????

posted on March 8, 2015
7. ## algerbra

can you plz explain 693 = 9x7x11 so we would need multipliers of 7 and 11 to yield a perfect square so 693x7x11 = 9x49x121 Thanks

posted on December 18, 2014
8. ## Calculus

Ohh I see. Thank you!

posted on September 30, 2014
9. ## Calculus

I'm a little confused though.. Where did you get the (1/7) and (1/5) in the second line?

posted on September 30, 2014
10. ## Calculus

Thank you Reiny!

posted on September 30, 2014
11. ## Calculus

Thanks Sarah!

posted on September 30, 2014
12. ## U.S/history AP

Hi, what are evidence of the 2 superpowers in the cold war.

posted on April 14, 2013

x+y=180 y= x+38 x+(x+38)= 180 2x+38=180 -38 =-38 2x = 142 x= 71 plug it in equation 71+71+38= 180 angle 1 = 71 angle 2 = 109

posted on September 6, 2012

angle 1= x angle 2=8x so 8x+x=180 9x=180 9x= 180 divided by 9 is 20 so x=20 angle 1=20 angle 2=160 Hope it helps :)

posted on September 6, 2012

You know complementary angles add up to 90 degrees so let x = one angle let 3x = the other angle x + 3x = 90 4x = 90 x = 22.5 degrees so one angle (x) is 22.5 and the other (3x) is (3 x 22.5) = 67.5

posted on September 6, 2012
16. ## Physics

the speed of sound in air is 343 m/s. using the relationship: 5280 feet in a mile, 3 feet in a yard and 3.3 feet in a meter. how many meters is this?

posted on September 3, 2012
17. ## pre- algebra

It's -5m not 5m

posted on May 19, 2011