# Questions Asked onAugust 9, 2012

1. ## physics 102

The output voltage of an AC generator is given by Δv = (180 V) sin (70πt). The generator is connected across a 13.0-Ω resistor. (a) By inspection, what is the maximum voltage? V (b) By inspection, what is the frequency? Hz (c) Find the rms voltage

2. ## biology

1.What is the % concentration of oil in the first, second, and third trophic levels in our food chain? 2.How did the concentration of oil change from one trophic level to the next? 3.How does the change in concentration represent biomagnification? 4.How

3. ## math

The stiffness S of a rectangular beam is proportional to its width (w) times the cube of its depth/height (h). find the dimensions (i.e.: w and h) of stiffest beam that can be cut from a log which has a circular cross-section with diameter of 12-in.

4. ## physics

Find the Magnitude of the force exerted by each cable to support the 625 N punching bag. One cable is connected to the ceiling with an angle of 37 degrees and the other cable is connected perpendicular to the side wall (Horizontal). HELPP

5. ## Chemistry

500ml of 0.250M Na2SO4 solution is added to an aqueous solution of 15.00 g of BaCl2 resulting in the formation of white precipitate of BaSO4. How many moles and how many grams of BaSO4 are formed?

6. ## physics

A copper block is removed from a 310 C oven and dropped into 1.10 kg of water at 20.2 C. The water quickly reaches 25.4 C and then remains at that temperature.what is the mass of the block?

7. ## physics

two objects are thrown from the top edge of a cliff with a speed of 10 m/s. one object is thrown straight down and the other straight up. if the first object hits the ground in 4.0 second, the second hits the ground in ________ seconds after the first

8. ## physics

A 150 N block is at rest on a table, a cable is connected from this block to another hanging off of the table. This block is 75 N. What is the magnitude of the minimum force of static friction on the 150 N block required to hold both blocks at rest? What

9. ## physics

A plane leaves Seattle, flies 84.0{\rm mi} at 21.0^\circ north of east, and then changes direction to 52.0^\circ south of east. After flying at 120{\rm mi} in this new direction, the pilot must make an emergency landing on a field. The Seattle airport

10. ## chemistry

Lime, CaO, is produced by the decomposition reaction CaCO3(s) ® CaO(s) + CO2(g). What weight of CO2 is obtained by the decomposition of 38.7 g of CaCO3?

11. ## Maths

A container in the shape of a right circular cone with vertex angle a right angle is partially filled with water. a) Suppose water is added at the rate of 3 cu.cm./sec. How fast is the water level rising when the height h = 2cm.? b) Suppose instead no

12. ## Chemistry

After 4.00 mol of C2H4(g) and 2.50 mol of Br2 (g) are placed in a sealed 1.0L container, the reaction reaches equilibrium and is written following: C2H4(g) + Br2(g) -> C2H4Br2(g) ... Calculate the equilibrium concentrations of all three substances.

13. ## physics

On a drive from your home to town, you wish to average 52 mph. The distance from your home to town is 106 miles. However, at 53 miles (half way), you ﬁnd you have averaged only 39 mph. What average speed must you maintain in the remaining distance in

14. ## Pre-Calculus

Which sets of ordered pairs represent functions from A to B? Explain. A = {a, b, c} and B = {0, 1, 2, 3} A. {(a, 1), (c, 2), (c, 3), (b, 3)} B. {(a, 1), (b, 2), (c, 3)} C. {(1, a), (0, a), (2, c), (3, b)} D. {(c, 0), (b, 0), (a, 3)} I narrowed it down to

15. ## chemistry

Zinc reacts with hydrochloric acid according to the reaction equation Zn(s)+2HCL(aq)=>ZnCl2(aq)+H2(g). How many mm of 1.50M HCL(aq) are required to react with 9.05 g of ZN?

16. ## math

Two trains heading toward each other are 400 miles apart. One train travels 15 miles per hour faster than the other train. If they arrive at the same station in 5 hours, how fast is each train traveling?

17. ## trig

(sec 8 x - 1)/(sec 4x -1) = tan 8x/tan 4x Prove it!

18. ## algebra

A tugboat goes 180 miles upstream in 15 hours. The return trip downstream takes 10 hours. find the speed of the tugboat without a current and the speed of the current

19. ## physics 102

three lamps connected to a 120-V AC (rms) household supply voltage. Lamps 1 and 2 have 75.0-W bulbs; lamp 3 has a 40.0-W bulb. (a) For each bulb, find the rms current. Irms, lamp 1 = A Irms, lamp 2 = A Irms, lamp 3 = A (b) For each bulb, find the

20. ## physics

Find the Magnitude of the force exerted by each cable to support the 625 N punching bag. One cable is connected to the ceiling with an angle of 37 degrees and the other cable is connected perpendicular to the side wall (Horizontal). HELPP

21. ## chemistry

Concentrated hydrochloric acid is a 38% solution of hcl in water and has a density of 1.18g/ml. How many milliliters of concentrated hydrochloric acid are needed to prepare 500ml of a 1:200 hcl solution? My calculation 500ml x 1:200 =2.5 1:200 means

22. ## chemistry

A stock solution containing Mn2+ ions was prepared by dissolving 1.168 g pure manganese metal in nitric acid and diluting to a final volume of 1.000 L. Calculate the concentration of the stock solution.

23. ## Public Health

All of the following are true of lead as an environmental hazard except? a. Paint in toys is an important potential source of lead exposure. b. The higher the blood lead levels the more severe the biological effects due to lead poisoning. c. Paint in homes

24. ## Chemistry

Assume that the ionic compound CaCl2, separates completely into Ca and Cl ions when it dissolves in water. How many moles of each ion are present in the solution???

25. ## Physics

A block of mass m has a spring –spring constant k and length L –connected, vertically, to the bottom. The block is dropped from height h, towards the floor. Assuming the spring is stiff enough that it does not compress fully at the floor, what is the

26. ## chemistry

Concentrated hydrochloric acid has specific gravity of 1.18 and 36% hcl weight. What volume of concentrated hcl must be diluted to give 50 gm of 10 percent. My calculation 50gm x 0.1 = 5gm 5gm x 36.5 = 182.5 182.5 / 0.36 = 506.9 506.9 / 1.18 = 430 ml This

27. ## physics

You can keep a 3 kg book from dropping by pushing it horizontally against a wall. What force must you apply to the book to keep it from falling? What is the coefficient of static friction?

28. ## biology

Trophic Level Cylinder Volume of H2O Volume of Oil Total Volume % Oil 1st 1000 ml 1000 ml 2nd 100 ml 100 ml 3rd 10 ml 10 ml

29. ## Art Appreciation

Discuss how art was used as a vehicle for propaganda, and whether such use is present in the works of Höch, Grosz, and Picasso. Use one example from Gardner's Art through the Ages and one from the Internet.

30. ## statistics (math)

The following equation can be used to predict the average height of boys anywhere between birth and 15 years old: y = 2.79x +25.64 where x is the age (in years) and y is the height (in inches). a. What does the slope represent in this problem? Interpret it

31. ## Physics

A body of mass 10kg moving with velocity 30m/s collide with another body of mass 15kg.If the velocity of both the body are same after collision.Then find their common velocity.

32. ## Child Development

Written observations of children as their behaviors occur in their context are termed:

33. ## Math

Given the following system is consistent x+y=1 tx+y=t (1+t)x+2y=3 Find the exact value of t.

In order to get an idea of significant subject areas in a chapter, it is best to read the: A. subheads. B. graphics. C. captions. D. table of contents.

35. ## consumer math

The Mannings file a tax return showing $125000 in earned income,$3288 from interest income, and they have a tax credit of 1% of their earned income. They claim 5 exemptions of $2500 each, one head of household exemption of$10500, pre-tax medical

36. ## physics 102

What are the wavelengths of electromagnetic wave in free space that have the following frequencies? (a) 3.00 10^19 Hz pm (b) 7.50 10^9 Hz cm

37. ## College Algebra

1. Use the Intermediate Value Theorem to show that the polynomial function has a zero in the given interval. f(x) = 13x^4 - 5x^2 +7x -1; [3,0] Enter the value of (-3). 2. Use the Intermediate Value Theorem to show that the polynomial function has a zero in

38. ## Politics/Debate

what does this sentence mean in regular english "The United States Federal Government should substantially increase development of domestic infrastructure." and what is the basic meaning of domestic infrastructure? Tahnk you soo much in advance!!

39. ## Physics

Box, mass m 1 , at rest against a compressed spring, spring constant k and compression of Δx, at the top of a ramp, height h, is released. It slides down the ramp, angle θ, with friction, coefficient μ. Half way down the ramp, it bumps into and sticks

40. ## math investment

8. (TCO A)  You can tax shelter only one-half of your retirement savings. You want to invest one-half of your savings in bonds and one-half in stocks. How much of the bonds and how much of the stocks should you allocate to the tax sheltered investment?

41. ## math

if the speed of a comet at perihelion (the closest orbital point to the sun) is 98000 mi/h. How far will the comet travel in 30 sec?

52. ## Physics

Some object moves 220.0 m at an angle of 42° north of west. During this motion, a 68.0 N force acts on the same object, doing +5460.0 J of work on the object. Assuming the force is applied horizontal to ground, what is this force’s orientation? Is there

53. ## algebra

I need help with doing this problem... 5x-7(2-4x). Any idea how to do it?

54. ## English

Is this sentence right? I have never had a pet before.

65. ## Chemistry

COmbination of nahco3andhcl what is before,after,mixture, and change?

66. ## Svience

I'm just courious what "ragweed mix" is/are. Is it one type of plant or a bunch?

67. ## algebra

A college bookstore ordered six boxes of red pens. The store sold 37 red pens last week and 67 red pens this week. 4 pens were left on the shelf. How many pens were in each box?

68. ## Am i right

Am i right? The question is how Paul Cezanne contributed to art. Is it, because he made his own style with how he used natural forms into shapes and such, and it influenced Picasso and Braque to create Cubism which later influenced others aswell?

69. ## Physics

The wind blows a 0.50 kg Styrofoam box, initially at rest, across level ground and then up an incline where it comes to a rest. The box slides 6.0 m on level ground before sliding up the 20.0 Ovincline. If the effective coefficient of friction between the

70. ## science

what is the kinetic energy of a ball with a mass of 5 kg rolling at 10 m/s

71. ## math

how do i change 0.26(2/3) to a fraction

72. ## Pre-Calculus

Determine whether the equation represents y as a function of x. |y| = 4 - x If I plug in 5, then I get -1, but it also means 1. Does that mean y has 2 values which means that it is not a function?

73. ## human services

how does a child's perspective change in middle childhood?

74. ## human services

what sex differences in mental abilities become evident in adolescence?

75. ## Chemistry

How many grams of CaSO4 are present in 320ml of a 0.00810 M solution of this compound?

76. ## statistics

Q) 75% of the population in Guinea, Africa is infected with malaria. Suppose a physician sees 6 patients in a given hour. Assuming these conditions are met, find the mean and standard deviation of the distribution. Help please!

77. ## microbiolab

what is the importance of using the McFarland standard?

78. ## ENGLISH

In the following sentence, what is the subject complement? My neighbor is a newspaper reporter.

79. ## math

If it takes 6 minutes to travel from Point A to Point B at a constant speed of 60 miles per hour, how many minutes does it take to travel the same route from point A to point B a constant speed of 50 miles per hour? I need an equation and a thorough/ clear

80. ## math

4000*136-5000 explain substraction

81. ## history

When postwar expansion slowed in the 1950s, an economic stimulus was provided by A. increased consumer goods manufacturing. B. Cold War spending. C. the construction of Levitt Towns. D. the baby boom.

82. ## English

What synonym of crumble can replace it in this sentence: "The town slowly crumbled"?

83. ## environmental science

describe three common challenges with managing non renewable energy sources.

84. ## Math

waht are lapse

85. ## Law

What is Jones Act (maritime area)?

86. ## Math

dear Ms.Sue what do they mean when they say find the tiime lapse.

87. ## Psychology

Describe in detail, the two methods of language acquisition?

88. ## Math

here is the problem Ms.Sue 6:32,9:29.

89. ## Child Development

Which perspective believe growth and development are primarily controlled by nature?

90. ## writing

when you write a sentence, how do you know what a verb, adj.or conjuction is?