Questions Asked on
March 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.

    asked by Wanda
  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

    asked by Amanda
  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

    asked by Lucy
  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

    asked by Amanda
  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?

    asked by JIM
  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

    asked by Chris Adison
  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

    asked by Anonymous
  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

    asked by Charlie
  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

    asked by Lucy
  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

    asked by Charlie
  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

    asked by Amanda
  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

    asked by Charlie
  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

    asked by Anonymous
  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

    asked by Jason
  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

    asked by Lucy
  16. Maths

    Many Thanks for your answer

    asked by Danial
  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!

    asked by Seymour
  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?

    asked by Chris Adison
  19. math-statistics

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

    asked by Stephanie
  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

    asked by Lucy
  21. chemistry

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

    asked by ss
  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?

    asked by karla
  23. Chem

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

    asked by Ginger
  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

    asked by Sandhya
  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?

    asked by Anonymous
  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.

    asked by Anonymous
  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

    asked by Emily
  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?

    asked by Matt
  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

    asked by Lucy
  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

    asked by Anonymous
  32. Math

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

    asked by Anonymous
  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

    asked by Anonymous
  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.

    asked by Anonymous
  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.

    asked by eddie
  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?

    asked by Lori
  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.

    asked by Lucy
  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

    asked by Lucy
  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

    asked by CJ
  40. Students and rubrics

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

    asked by Sarah
  41. secience

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

    asked by tonya
  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.

    asked by Lucy
  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

    asked by Lucy
  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?

    asked by Anonymous
  45. Scientific notation

    what is .020833333 in scientific notation?

    asked by Jon
  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?

    asked by Lucy
  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

    asked by Anonymous
  48. R.E/history

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

    asked by Kelly
  49. physical education

    what are sports that is related in turks and caicos island

    asked by levonjah
  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"

    asked by Jason
  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?

    asked by Anonymous
  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?

    asked by Morgan
  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

    asked by Jackie
  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

    asked by Karla
  55. Algebra

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

    asked by Shondell
  56. research

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

    asked by Anonymous
  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

    asked by Seymour
  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!

    asked by Martin
  59. Math

    Graph the function x if -2

    asked by Jimmy
  60. Physics

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

    asked by Sandhya
  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! :)

    asked by Pan
  62. Science-Please Help!

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

    asked by Haya
  63. english

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

    asked by Eleanor
  64. science

    need information on patricia ann bianconi background

    asked by patty
  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.

    asked by April
  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

    asked by amy
  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?

    asked by Tim
  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

    asked by Lucy
  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

    asked by Morgan
  70. arithmetic

    I am having a problem with ratio's

    asked by KIm
  71. Rubrics

    What are performance indicators? What is the difference between a rubric and a performance indicator?

    asked by Sarah