# Questions Asked onMarch 29, 2008

1. ## IB Math SL

The triangle ABC is defined by the following information. Vector OA = (2, -3), vector AB = (3, 4), AB and BC are perpendicular, and vector AC is parallel to (0, 1). Draw a diagram of triangle ABC. Write down the vector OC.

2. ## Physics

The intensity due to a number of indipendent sound sources is the sum of the individual intensities. A) When four quadruplets cry simultaneously, how many decibels greater is the sound intensity level than when a single one cries? B) To increase the sound

3. ## Algebra II

Use log5(2)=0.4307 and log5(3)=0.6826 to approximate the value of log5=54. According to the example in my book I would divide 0.6826 by 0.4307 and the answer is 1.5848 but this is not one of the answers given. My choices are: a) 0.1370 b) 2.4785 c) 0.8820

4. ## Physics

swimming duck paddles the water with it's feet once every 1.6s, producing surface waves with this perios. The duck is moving with constant speed in a pond where the speed of the surface waves is 0.32m/s and the crests of the waves are 0.12m apart. A) What

5. ## PHYSICS

A ball of mass 0.150kg is dropped from a height of 1.25m. It rebounds from the floor to reach a height of 0.960m. What impulse was given to the ball by the floor?

6. ## Physics

Transcranial magnetic stimulation (TMS) is a noninvasive technique used to stimulate regions of the human brain. A small coil is placed on the scalp, and a brief burst of current in the coil produces a rapidly changing magnetic field within the brain. The

7. ## math

This is an SAT question of the day that I can't understand. The sum of the digits of a three-digit number is 12. If the hundreds digit is 3 times the tens digit and the tens digit is 1 over 2 the units digit, what is the tens digit of the number? Answer

8. ## Physics

A cannon shoots a shell straight up. It reaches its maximum height, 1,051 feet, and splits into two pieces, one weighing 2 lb and the other 4 lb. The two pieces are observed to strike the ground simultaneously. The 4 lb piece hist the ground 1,608 feet

9. ## Algebra II

Write the equation log243(81)=4/5 in exponential form. My answer is 243^4/5=81. Evaluate 9^log9(54). My answer is 6. Are these correct?? Thanks

10. ## Physics

A cannon shoots a shell straight up. It reaches its maximum height, 837 feet, and splits into two pieces, one weighing 2 lb and the other 5 lb. The two pieces are observed to strike the ground simultaneously. The 5 lb piece hits the ground 1,564 feet away

11. ## Physics

Two identical violin strings, when i tune and stretched with the same tension, have a fundamental frequency of 440Hz. One of the strings is retuned by adjusting the tension. When both strings are pluckes simultaneously, after one has been retuned, 1.5

12. ## Physics

A cannon shoots a shell straight up. It reaches its maximum height, 1,051 feet, and splits into two pieces, one weighing 2 lb and the other 4 lb. The two pieces are observed to strike the ground simultaneously. The 4 lb piece hist the ground 1,608 feet

13. ## Math - explanation

This is an example in the text book. Using vectors, demonstrate that the three points A(5, -1), B(-3,4) and C(13,-6) are collinear. Solution AB = (-8, 5) BC = (16, -10) Then BC = 2AB AB and BC have the opposite direction, so the points A, B, and C must be

14. ## chemistry

1) If the kelvin temperature of a gas sample in a steel tank increases to three times its original value , what will happen to the pressure? I think It will increase. Is this correct? By what factor does the gas pressure change? 2) A gas sample at a

15. ## Algebra II

Log6(6^9)=??? Answer: 9 Ine^-3x=??? Answer: -3x Use log5(2) = 0.4307 and log5(3) = 0.6826 to approximate the value of log5(12) Answer: log5(2) + log5(3)=log5(2^2*3) 2(0.4307) + 0.6826=1.544 so approximate value of log5(12)=1.544 I appreciate your checking

17. ## Music

What form is the first movement of Mozart Piano Concerto No 21 K. 467 in? Is it sonata allegro? Please someone help me out, I have to write a music paper and I have very little technical expertise in the subject!

18. ## physics induced voltage

A Boeing 747 jet with a wingspan of 60.0 m is flying horizontally at a speed of 287 m/s over Phoenix, Arizona, at a location where the Earth's magnetic field is 50.2 µT at 58.0° below the horizontal. What voltage is generated between the wingtips?

19. ## math-statistics

18) Which of the following is the most significant result? A) P

20. ## Algebra II

last 2 for tonight Express log6(19) in terms of common logarithms. Then approximate its value to four decimal places. Answer: log19/log6=1.6433 In a certain area, the sale price of new single-family homes has increased 4.1% per year since 1992. If a house

21. ## chemistry

How can you tell if a compound consists of ions if it does not dissolve in water?

22. ## physics

I keep seeing 7.620497955 as the electrical force between a proton and electron but when I multiply (8.99 x 10^9)(1.602 x 10^-19)-(1.602 x 10^-19)/(10^-10)2 I get a diffrent answer. Am I multiplying the wrong numbers?

23. ## Chem

Is this half-reaction H2(g) + 2 OH-(aq) ===> 2 H2O(l) = 2 e reduction or oxidation?

24. ## Physics

For a L-C-R circuit Vin = v0*expjwt. Vout is taken across R a) Calculate the impedance of the circuit measured from the input side. Express the impedance in polar form. b) Calculate the gain=Vout/Vin and express the ratio in polar form. c) Sketch the

25. ## 12 Chemistry

What is the molar enthalpy of combustion of magnesium? This was the lab question that I was asked to find after performing a lab based on Hess' law. I can't find anywhere in my notes how to calculate this, and the text book doesn't explain their steps

asked by Chase (sorry if this long)
26. ## math

Calculate the magnitude of a when a = (2, 3, -2). Find (1/|a|)xa. Is it a unit vector. I calculated the |a| = sqrt17. I don't know how to determine if it's a unit vector or not?

27. ## Algebra

Solve Find (f o g)(-6) when f(x)=4x+4 and g(x)=6x^2-3x-6. I originally came up with 918, but the answer is 916. Obviously I was close, but could someone tell how to get 916. I am studying for a test and am re-working my homework problems. Thanks.

28. ## Physics

I don't know if my other post went through or not, so I'm reposting it here. The first question I didn't know the answer to and the second one was worded in a way that I couldn't understand. 1. With respect to an electric and a magnetic field, how does the

29. ## Math

I am thinking about going back to college and taking online math classes. I am eligible to take either financial mathmatics or contemporary math. But I am not really sure what the difference is between them. Is there one that is more easy than the other?

30. ## Algebra II

I cannot figure out how to work this one. I have tried working it like the example in the book but cannot come up with one of the answers given. Please help. Use log5(2)=0.4307 and log5(3)=0.6826 to approximate the value of log5=54. According to the book's

31. ## French

Could you please tell me if is this correct? "Plusieur des grands magasins de New York ont...." I have read elsewhere that after adverbs of quantity one uses DE; and also that if the (plural) noun is preceded by an adjective one uses DE instead of DES. I

32. ## Math

Can the sum of two unit vectors be a unit vector? Can the difference?

33. ## Vectors

I have a test on monday and I need help with these two questions, please. 1)Prove that the magnitude of the vector OP = (a,b,c) is given by |OP| = sqrt a^2+b^2+c^2 I understand how to find the magnitude, but I don't know how to prove it. 2)Give a

34. ## Math

Find a single vector equivalent to each expression below. a) 5(0, -2, -4) - 4(3,8,0) Please show me all steps so I can understand it.

35. ## social psychology

representation of violence in the media? Qualitative approach: Title- abstact brief summary of project - Introduction plus a research questionreview the relevant literature leading up to the research question- justify the use of your methodology.

36. ## Algebra

I don't know which is which y=(x+9)^2-3 I know it is all real numbers, but i don't know if my answer should be [-3,00) or (-9,00) Can some one explain this?

37. ## Algebra II

Solve, round to four decimal places if necessary: log4(x-9)=2 Answer: x-9=4^2 x-9=16 x=11 log4(z)+log4(z-3)=1 Answer: z+z-3=1 2z=4 z=2 Thanks for checking my work.

38. ## Algebra II

Solve, round to 4 decimal places if necessary: 3.9^m-4=10.21 Answer: (m-4)In(3.9)=In(10.21) m(In3.9)-4(In3.9)=In(10.21) m=(In10.21)+4(In3.9)/In3.9 m=7.7672/1.3609 m=5.7074 e^3x>=21 Answer: Ine^3x>=21 3x=In21 x=In21/3 x=1.0148 Thanks

39. ## English

I am just curious if you know of any one I could submit an English Essay to. It is less than one page and I need someone to check grammar, spelling etc.... I didn't think this site would accept something like that but was wondering if you know of a website

40. ## Students and rubrics

How can students be involved in understanding and using rubrics to help with their learning?

41. ## secience

describe how at least one fossil fuels and minerals is formed from its sources

42. ## Algebra II

Please check answers: Use the equation of the exponential function whose graph passes through the points (0,-2) and (2,-50) to find the value of y when x= -2. My answer: -2/25 Solve 64^x/=5/2 Thanks.

43. ## Algebra II

Please check the following: Solve log4(m-3)+ log4(m+3) =2 Answer: 1 Solve 6^3n=43^5n-4 Answer: 1.1202 Solve 5^2x+1>=50 Answer:x>=4.5000 Use common logarithms to approximate log9(207) to four decimal places. Answer: 2.4270 Ealuate: In e^-9x Answer: -9x

44. ## Math

Use the cross product to find a vector perpendicular to each of the following pairs of vectors. (2, -1, 3) and (1, 4, -2) Can someone please explain this step by step?

45. ## Scientific notation

what is .020833333 in scientific notation?

46. ## Algebra II

Solve log2(7x-3)>= log2(x+12) My work: 6x=15 x=15/6 x-5/2 so my answer would be: x>= 5/2 Is this correct?

47. ## Math

If a = 3i + 2j - k and b = -2i + j calculate each magnitude. a) a + b I got sqrt3, but the answer at the back of the book says sqrt11. 2) If D(3,4,5) and E(-2,1,5) are points in space calculate each expression and state what it represents. |OD| can you

48. ## R.E/history

Why did the Romans invade Palestine in the time of Jesus?

49. ## physical education

what are sports that is related in turks and caicos island

50. ## chemistry

why does a weather balloon get bigger as as it rises from Earth's surface? I don't understand how this relates to "kinetic molecular theory"

51. ## Math

Find the dot product of the following vectors: a = (4, 1) b = (-1,4) a = (7,8) b = (4, -7) You have to find the angle too. Can someone please do these?

52. ## statistics

90% of adults drink milk. A sample of adults in an area was taken. 657 of 750 drink milk. Do these responses provide strong evidence that the 90% figure is not accurate for this region? I figured it out and got the P-value to be .028 How do I explain this?

53. ## Marketing

T/F Malibu Beach Parties finds that the tastes and preferences of its customers change more rapidly than in the past. The manager is constantly looking for external ideas from customers, suppliers, competition, and the sales force I think this answer is

54. ## physics

By "see" I meant that I had checked my answer on the internet to see if I was correct in thinking that multipying the charge of an electron, charge of a proton, and k would yield the electrical force between an electron and proton. My answer was 23.10 x

55. ## Algebra

How do you solve -3/4 divide by 1/10

56. ## research

Could someone help me find reliable websites (not Wikipedia, etc) that explains that ribosomes are membrane-bound organelles?

57. ## More Music

Okay, so I'm getting the hang of this. Anyway, the first "Theme" of Mozart's 21st Piano Concerto is plain to me. But where does the second begin? And what is it? Again, I have to write a paper on this, and besides a VERY basic, rudimentary comprehension, I

58. ## Microecon

Hi, I've got a question about producer surplus. I know that the magnitude of producer surplus would depend on the elasticity of supply, but i don't know why... Please explain. Thank you!

59. ## Math

Graph the function x if -2

60. ## Physics

Do circular electric lines of force exist ? why? what about magnetic lines of force? Pl help

61. ## Calculus

Find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the x-axis. y=ln x, y=0, x=1, x=3 Please show the steps in your work, thanks! :)

name two devices that we use on earth, which use the same principles as space capsules. Explain for each one.

63. ## english

I have to write a 3 page essay on "Is Tradition a Neurosis?" Any ideas please?

64. ## science

need information on patricia ann bianconi background

65. ## law

I was just wondering if someone could give me a little insight on where to begin. You receive an e-mail from your supervisor about her attendance at the upcoming city council meeting to request an increased budget for sex offender rehabilitation programs.

66. ## biological psychology

If a Manatee and a Californian Sea lion's Brain are roughly the same size whihc mammel will have a cerebal cortex with a larger surface area and why? How does this reflect the different feeding habits of the mammels? thank you

67. ## Algebra

h(x)=5/x^2+6 I know the answer is: f(x)=x+6, g(x)=5/x^2, but I do not know how to get it. Can someone help me understand it?

68. ## Algebra II

Simplify: (x^5)(x^pi) Answer: x^5+pi x=8.14 Round to 4 decimal places if necessary: (1/5)^t-2 = 125 (5^-1)^t-2=125 5^-t+2=5^3 -t+2=3 -t=1 t= -1

69. ## History

I am making a poster on the cold war. I wanted to make the background look like cracked ice, like on a lake. I thought I could do the whole "cold" thing. I wanted to put a phrase on part of it. Somthing like how they were on thin ice, and close to breaking