# Donald

Newest questions and responses by Donald
1. ## physics

A bullet of mass 0.045kg is fired from a gun of mass 9kg, the bullet moving with an initial velocity of 200m/s. Find the initial backward velocity of the gun.

2. ## physics

estimate number of impacts number of imapcts air molecule make with palm of your hand assuming all air is nitrogen molar mass =.0028

3. ## Math

Write the ratio as a fraction in lowest terms. 1 1/7 to 3 1/4

4. ## Math calculus

(2) (-1) (3)+(4)

5. ## Math A Calculus

For a =( 2 ÷3)and b=(-1÷4)..Find a).. a+b b).. | a+b | c).. Find the length of the vector i + 2j-- 2k

6. ## Math

An aircraft has airspeed of 300km/h and it's course is 020°. The speed of the wind is 80km/h blowing from 320°..sketch the diagram to represent this information (ie: the triangle of velocities).

7. ## Math

A man walk 9km in the direction 246 degrees and then for 6km in the direction 096 degrees...... What is the displacement from the starting point?..... Formula and answer please?

8. ## Math

A man walk 9km in the direction 246 degrees and then for 6km in the direction 096 degrees.... What is the answer in diagram Form?

9. ## Math

Good evening. I posted a math question earlier that I never received any help on because someone posted something inappropriate. My new math problem is as follows: The area of a rectangular piece of a land is 3/16 square miles. If the width of the piece of

10. ## Math

Ricardo has a \$50.00 gift card for an electronics Store. He also has a coupon good for \$10 off his Purchase. Let a represent the amount of merchandise Ricardo can buy from the store using his gift card and coupon. Graph the solution set for a on the number

11. ## Science

In what levels are producers and tertiary consumers, respectively found in an energy pyramid? I am kind of lost on how I am supposed to determine what level a producer is at on a pyramid? Can you please help me with this.

12. ## Science

Which level of consumer is an owl in the following chain: grass, cricket, mouse, and owl? I do not know understand this at all can you please explain this so I can get a better understanding of this?

13. ## Science

What factor is described when low water levels are causing animals to die from dehydration? I am confused on this. Please help. I don't even know where to begin looking

14. ## Math

Mrs. Sue, I have a math question if you can please help me on this. I am confused. I am doing coordinates. If I have a theater at 5 and a Restaurant at -4 (5,-4) how do I find out the halfway point in between?

15. ## chemistry

Explain the first ionization energy of lithium is greater than that of sodium

16. ## chemistry

How many unpaired electrons for cr3+

17. ## Math

Good evening everyone. I am very confused on how to work on the below problem. Ingrid walked her dog and washed her car. The time she spent walking her dog was 1/4 the time it took to wash her car. It took Ingrid 14 minutes to walk the dog. How long did it

18. ## math

write equation of hyperbola with cebter c(4,2) vertex (4,5) equation of one asymptote 4y-3x=-4

19. ## chemistry

Calculate the energies of the states of hydrogen atom with n=2 and n=3

20. ## chemistry

Calculate the energy required for ionization of electron from the ground state of hydrogen atom

21. ## chemistry

Calculate the energy required for ionization of electron from the ground state of hydrogen atom

22. ## chemistry

Calculate the maximum number of unpaired electrons that can be placed in a 6d subshell

23. ## science

Explain the purpose of a control in a scientific experiment

24. ## science

If a scientist wished to to determine the effect of a certain herbicide on wee growth he would include a control in the investigation. Suggest a suitable control in this case.

25. ## science

Describe how you would investigate effect of ph on enzymes rate. Draw a labelled diagram to show how you carried out the experiment

26. ## science

Explain how end product inhibition can control enzyme activity in living cells

27. ## science

What is the unit for measuring enzyme activity? What is turnover number

28. ## math

A circle has centre(5,12) and its tangent to the line with equation 2x-y+3=0. Wtite equation of the cirle

29. ## math

A circle has centre(5,12) and its tangent to the line with equation 2x-y+3=0. Wtite equation of the cirle

30. ## math

The locus of point whose distance from the point (0,5) is always 3/4 of its distance from line y=8 is an ellipse. Find major and minor axis

31. ## Math

Hello I need to ask a question. This is all new to me as we are just learning this in school. How would I write an inequality with -197 and -110? I have never done this before. Can you please help me?

32. ## Language Arts

Good evening. I have a problem in English Language Arts. I have to write a poem. The instructions are as follows: Write a short poem that reflects the mood you interpret of a season (Spring, Summer, Fall or Winter). Follow the requirements listed below: 1.

33. ## Math

Combine like terms. 7a square root 2 - a square root 2 + 16= My answer would be as follows: 7a square root 2 + 16 Can you please check to see if I got this correct

34. ## Math

Combine like terms. 6b plus 7b-10= Would I add 6b + 7b=13b-10 13b-10=3b? Would this be correct? Please advise.

35. ## Math

Combine like terms. 32y plus 5y= I don't know what to do. I don't understand this. Please help.

36. ## Math

Question. I have some math problems that I really need help with and this is all new to me. The direction are as follows: Combine like terms 7x4 -5x4 the number four is square root. I don't understand at all what to do. Please help.

37. ## Math

Evaluate the following expression: (2 x 3)>2 - 5>2 The answer I got was 11...How I got this answer was 6 x 6 = 36 and 5 x 5 = 25 then I subtracted 36-25=11`

38. ## math

Use the distributive property to write an expression that is equivalent to the example below: 5(2x + 7) I think my answer is... 45.....How I got this answer was 5 x 2 + 5 x 7=45 10 + 35 = 45 Can you please double check my work?

39. ## Math

Which of the following is equivalent to the expression 6m + 3? A)2(3m + 3) B)3(2m + 1) C)3(2m + 3) D)6(m + 3) The answer I got was B) 3(2m + 1). How I got this answer was 3 x 2 + 3 x 1 = 6m + 3.

40. ## Math

How do you write at least 6 fractions from the below ingredients list that serves 4 people. 1 cup all-purpose flour 2 eggs 1/2 cup milk 1/2 cup water 1/4 teaspoon salt 2 tablespoons butter , melted How do I make these fractions? PLEASE PLEASE PLEASE PLEASE

42. ## Math

Write each percent as a fraction and as a decimal. 7. 72% full 72/100 or .72 9. 500% increase Would it be 500/100 or 500/1000? .500 11. 37% profit 37/100 and .37 Please be so kind as to double check my answers and explain to me if I got anything wrong so I

43. ## Science

The above is an article which I had to read for homework and one of the questions that I have to answer is as follows: Which bucket(s) could be supported with evidence from this Document? I do not understand this at all. Please help me.

44. ## Science

For many years it was believed by geologists that the location of the continents was fixed.These scientists believed that the locations of the continents was determined many billions of years ago,as the young Earth cooled down from its original state as a

45. ## algebra

5digit palidrone 6 - - 5 multiple of 9

46. ## life orantation

Make six suggestions on how to combat the violations of human rights identified by you in the previous questions and indicate any organisations you have come about in your research and indicate how they combat the discriminations.

47. ## Math

When looking at the problem given in the Video Example 84 –Factoring Out the Opposite of the GCF, located in the media section of Chapter 5, what GCF is first factored out of all terms in the expression

48. ## algebra

a woman drove a distance of 240km on the return journey she drove 20km/h faster and took two hnurs less. what was her speed on the outward journey?

49. ## Math

how many hours will it take Wendy to make 4 2/3 batches of cookies if she can make 1 1/3 batches in 1 hour

50. ## Chemistry

please balance this chemical equation iron +oxygen > iron (III) oxide +energy Fe + O2> Fe2 O3 + heat and light

51. ## Lang Arts

The novel to kill a mockingbird feature a main character named scout. Scout is also the voice that tells the story. What point of view is used in the novel? A.First Person B.Third-Person Limited

52. ## Peter nchabeleng

If you live only 800m away from the school. If she leaves her home at the sametime as Constance, how many minutes before Constance will she arrive

53. ## Peter nchabeleng

If you live 3,5 km away from school. How long will it take you to walk to school

54. ## Life sciences

Why are the fossils kept in a glass box in the museum?

55. ## Statistics

Find the range and the standard deviation (correct to two decimal places). 77, 89, 96, 96, 102

56. ## Finance

Jared has decided that he wants to build enough retirement wealth that, if he invests at 8% per year (compounded monthly), will provide him with \$3,500 of monthly income for 30 years. To date, he has saved nothing, but he still has 25 years until he

57. ## Finance

Mark has won a contest in which he will receive \$10,000 at the end of each of the next 10 years and then \$20,000 a year for the next 30 years after that. With an 8% discount rate, what is the present value of Mark's prize?

58. ## Finance

You borrow \$150,000 to purchase a new house. The bank offers you a special 20 year loan with a 7% interest rate and you will make annual payments. How large will each payment be? If you want to sell your house after 7 years, how much will you owe and need

59. ## Math Geometry

Marisol is painting on a piece of canvas that has an area of 180 square inches. The length of the Painting is 1 1/4 times the width. What are the dimensions of the painting this is for elementary school so make it simple

60. ## Math Geometry

Marisol is painting on a piece of canvas that has an area of 180 square inches. The length of the Painting is 1 1/4 times the width. What are the dimensions of the painting

61. ## Math

If I swam 30 meters in 16 seconds how would I express this in a fraction? 16/30 or 30/16 and why?

62. ## Physics

Consider the static equilibrium diagram below. What is the net force acting along the positive x-axis?

63. ## physics

In the process of electrolysis, electrical power is used to separate water into oxygen and hydrogen molecules via the reaction: H2O --> H2 + ½O2 This is very much like running a hydrogen fuel cell in reverse. We assume that only the activation potential

64. ## Math2

A "quick picture" is an estimate than? 5 x 2.7 ..... 5 x 3= 15 Its been a long time since elementary school and I do not remember "quick picture" The question was How can you use a "quick picture" to find 5 x 2.7? the answer is 13.5.......an estimate would

65. ## Math

How do you use a "quick picture" to find 5 x 2.7.

66. ## science

An analysis for copper was performed on two pure solids. One solid was found to contain 43.0% copper; the other contained 32.0% copper. Could these solids be samples of the same copper-containing compound?

67. ## Algebra

How do I find the unknown digit to make this statement true 2.48 > 2.4 ____1 > 2.463

68. ## Maths - Probability q2

Five cards are lettered A, B, C, D, E Three cards are chosen at random one after the other without replacement and are in the order shown below First, Second, Third What is the probability that the cards spell the word BED

69. ## Math - Probability

in a primary school 70% of the boys and 55% of the girls can ride a bicycle. if a boy or a girl are chosen at random, what is the probability that both of them can ride a bicycle?

70. ## math

in a primary school 70% of the boys and 55% of the girls can ride a bicycle. if a boy or a girl are chosen at random, what is the probability that both of them can ride a bicycle?

71. ## enlish

correc the following sentences for subject-verb agreement,tens and fragment. 1. My cat it is very playful 2. when he thought he could afford to pay his own school fees. 3. This children keep making noise. 4. These are great news indeed; i can`t believe i

72. ## Physics

The drawing shows six point charges arranged in a rectangle. The value of q is 9.27 µC, and the distance d is 0.17 m. Find the total electric potential at location P, which is at the center of the rectangle.

73. ## Physics

Two particles each have a mass of 5.5 10-3 kg. One has a charge of +4.8 10-6 C, and the other has a charge of -4.8 10-6 C. They are initially held at rest at a distance of 0.88 m apart. Both are then released and accelerate toward each other. How fast is

74. ## Physics 1

The skateboarder in the drawing starts down the left side of the ramp with an initial speed of 5.4 m/s. If nonconservative forces, such as kinetic friction and air resistance, are negligible, what would be the height h of the highest point reached by the

75. ## ecoomics

If the multiplier is 4, a \$10 billion increase in autonomous investment will cause a

76. ## physics

In attempting to pass the puck to a teammate, a hockey player gives it an initial speed of 1.1 m/s. However, this speed is inadequate to compensate for the kinetic friction between the puck and the ice. As a result, the puck travels only one-half the

77. ## physics

One of the new events in the 2002 Winter Olympics was the sport of skeleton (see photo). Starting at the top of a steep, icy track, a rider jumps onto a sled (known as a skeleton) and proceeds-belly down and head first-to slide down the track. The track

78. ## physics

The skateboarder in the drawing starts down the left side of the ramp with an initial speed of 5.4 m/s. If nonconservative forces, such as kinetic friction and air resistance, are negligible, what would be the height h of the highest point reached by the

79. ## Physics

A 7410-kg satellite has an elliptical orbit, as in the figure. The point on the orbit that is farthest from the earth is called the apogee and is at the far right side of the drawing. The point on the orbit that is closest to the earth is called the

80. ## Physics

A fighter jet is launched from an aircraft carrier with the aid of its own engines and a steam-powered catapult. The thrust of its engines is 2.10 105 N. In being launched from rest it moves through a distance of 87 m and has a kinetic energy of 4.30 107 J

81. ## Physics

A 0.069-kg arrow is fired horizontally. The bowstring exerts an average force of 65 N on the arrow over a distance of 0.95 m. With what speed does the arrow leave the bow?

82. ## Physics

A cable lifts a 1060-kg elevator at a constant velocity for a distance of 39 m. What is the work done by each of the following?

83. ## Physics

Each of the space shuttle's main engines is fed liquid hydrogen by a high-pressure pump. Turbine blades inside the pump rotate at 595 rev/s. A point on one of the blades traces out a circle with a radius of 0.02 m as the blade rotates. (a) What is the

84. ## Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight?

85. ## physics

The blade of a windshield wiper moves through an angle of 90.0° in 0.31 s. The tip of the blade moves on the arc of a circle that has a radius of 0.59 m. What is the magnitude of the centripetal acceleration of the tip of the blade?

86. ## Physics

In the figure below, an object, after being released from its circular path, travels the distance OA in the same time it would have moved from O to P on the circle. The speed of the object on and off the circle remains constant at the same value. Suppose

87. ## Physics 1

The drawing shows a wire tooth brace used by orthodontists. The topmost tooth is protruding slightly, and the tension in the wire exerts two forces and ' on this tooth in order to bring it back into alignment. If the forces have the same magnitude of 15.0

88. ## Physics 1

The helicopter in the drawing is moving horizontally to the right at a constant velocity. The weight of the helicopter is W = 55600 N. The lift force generated by the rotating blade makes an angle of 21.0° with respect to the vertical. (a) What is the

89. ## Physics

In the drawing, the weight of the block on the table is 384 N and that of the hanging block is 195 N. Ignore all frictional effects, and assuming the pulley to be massless. (a) Find the acceleration of the two blocks. m/s2 (b) Find the tension in the cord.

90. ## chemistry

What is an open and closed sytem refer to in chemistry? thanks!

91. ## Physics

An electron is a subatomic particle (m = 9.11 10-31 kg) that is subject to electric forces. An electron moving in the +x direction accelerates from an initial velocity of +5.16 105 m/s to a final velocity of +2.23 106 m/s while traveling a distance of

92. ## physics

A 1720-kg car is traveling with a speed of 15.0 m/s. What is the magnitude of the horizontal net force that is required to bring the car to a halt in a distance of 47.0 m?

93. ## physics

A 1720-kg car is traveling with a speed of 15.0 m/s. What is the magnitude of the horizontal net force that is required to bring the car to a halt in a distance of 47.0 m?

94. ## physics

Several people are riding in a hot-air balloon. The combined mass of the people and balloon is 328 kg. The balloon is motionless in the air, because the downward-acting weight of the people and balloon is balanced by an upward-acting 'buoyant' force. If

95. ## physics

Three uniform spheres are located at the corners of an equilateral triangle. Each side of the triangle has a length of 3.10 m. Two of the spheres have a mass of 3.20 kg each. The third sphere (mass unknown) is released from rest. Considering only the

96. ## physics

A space traveler weighs 635 N on earth. What will the traveler weigh on another planet whose radius is three times that of earth and whose mass is twice that of earth?

97. ## Physics

(a) Calculate the magnitude of the gravitational force exerted on a 488-kg satellite that is a distance of 1.95 times earth radii from the center of the earth. (b) What is the magnitude of the gravitational force exerted on the earth by the satellite? (c)

98. ## Physics

A bowling ball (mass = 7.2 kg, radius = 0.14 m) and a billiard ball (mass = 0.40 kg, radius = 0.028 m) may each be treated as uniform spheres. What is the magnitude of the maximum gravitational force that each can exert on the other?

99. ## Physics

Airplane flight recorders must be able to survive catastrophic crashes. Therefore, they are typically encased in crash-resistant steel or titanium boxes that are subjected to rigorous testing. One of the tests is an impact shock test, in which the box must