Science & Mathematics - 5 December 2007

i need the answer to the question

2007-12-05 14:30:03 · 7 answers · asked by Anonymous in Mathematics

2007-12-05 14:28:16 · 4 answers · asked by Anonymous in Mathematics

a stationary motion detector sends sound waves of frequenct 0.150 MHz toward a truck approaching at a speed of 45.0 m/s. What is the frequency of the waves reflected back to the detector?

Explain your work. Thanks! :)

2007-12-05 14:24:16 · 1 answers · asked by Anonymous in Physics

Hello, does anybody know how to do this?

Integral sign with e on top and L on bottom. (2+ln x)to the power of 3 divide all of that by 5x ??????

thank you in advance.

2007-12-05 14:22:33 · 2 answers · asked by Anonymous in Mathematics

What Species Is This Spider?

http://s136.photobucket.com/albums/q161/migasa74/34%20Colombia/?action=view¤t=CARTAGENA12y11deenerode2006314.jpg

2007-12-05 14:20:45 · 2 answers · asked by thirsty_for_blood 1 in Zoology

If
Pi1: 3x-2y+z-5=0
Pi2: x+y - 2z +3=0

If the two planes are not parallel, what is the equation of the intersection line?

2007-12-05 14:20:26 · 3 answers · asked by Mayx 3 in Physics

2007-12-05 14:19:32 · 2 answers · asked by melly 1 in Earth Sciences & Geology

2007-12-05 14:19:32 · 3 answers · asked by Anonymous in Earth Sciences & Geology

A total of 50 juniors and seniors were given a mathematics test. The 35 juniors attained an average score of 80 while the 15 seniors attained an average of 70. What was the average score for all 50 students who took the test?

A. 73
B. 75
C. 76
D. 77
E. 78

2007-12-05 14:18:44 · 6 answers · asked by Astro J 1 in Mathematics

which equation do you use? and are the planets radius's necessary.?
thanks a bunch!!!!

2007-12-05 14:17:50 · 7 answers · asked by chickloombaa 2 in Astronomy & Space

2. Anne and Bill are watching a hot air balloon as it rises straight up from its launching pad in a flat field. At 1:30 the bottom of the balloon gondola is 47 feet above the landing pad and rising at a rate of 54 feet per minute. Anne is standing still on top of a 12 foot high ridge and is 38 feet west of the path of ascent. Bill is in the field 29 feet north of the pad and walking toward it at a rate of 78 feet per minute.
Anne’s eye level is at 5 feet. Let α be the angle of elevation as
Anne looks at the bottom of the gondola. Bill’s eye level is at 6 feet. Let β be the angle of
elevation as Bill looks at the bottom of the gondola.

2007-12-05 14:16:55 · 1 answers · asked by Anonymous in Physics

Okay I admit I'm really old school but my arithmetic doesn't jive with the powers that be. I am a level 1 and I have been on this site for three days. I have answered all the questions they allow me per day, so why do my stats say I've only asked 56 questions? Each day so far I get that 'you've reached your limit' message just as I reach a question I can get my teeth into. Whats up with this? Is my arithmetic wrong or is the computers, in my old one room schoolhouse three times twenty is '60' not 56. Any help would be appreciated. Apparently I'm only semi literate.

2007-12-05 14:15:52 · 1 answers · asked by Mike S 7 in Mathematics

If Pi1: 2x-6y-z+12=0 and Pi2: -6x+18y+3z+10=0

Calculate the distance between Pi and P2

2007-12-05 14:15:37 · 1 answers · asked by Mayx 3 in Mathematics

how can you tell if a bond is polar or nonpolar and how can you tell if a kind of molecule is polar or nonpolar. how do you determine the spape of the molecule( linear, bent, pyramidal, tetrahedral) can you explain how you know if an electron-dot formula is correct? I sort of know how to do this, but just not to sure.
.. ..
:Cl:Cl: is this correct?
" "
O::O is this correct?

2007-12-05 14:12:38 · 3 answers · asked by kukinney26 2 in Chemistry

If the world ends, and there are 100,000 people left on the earth, which types of engineers will be most valuable in helping to rebuild civilization?

2007-12-05 14:10:18 · 12 answers · asked by Anonymous in Astronomy & Space

2007-12-05 14:07:39 · 4 answers · asked by Gater 1 1 in Astronomy & Space

2007-12-05 14:05:14 · 4 answers · asked by Anonymous in Astronomy & Space

An ideal gas is in contact with a heat reservoir so that it remains at a constant temperature of 300 K. The gas is compressed from a volume of 33 L to a volume of 18 L. During the process the mechanical device pushing the piston to compress the gas is found to expend 7 kJ of energy. What is the magnitude of the heat flow between the heat reservoir and the gas in kJ?

2007-12-05 14:04:28 · 2 answers · asked by hehasnoidea2001 2 in Physics

Can anyone please explain these formulas and the law for me. I'm in AP Bio and my teacher sucks, and I have no idea what to do. Thanks.

2007-12-05 14:02:39 · 3 answers · asked by Anonymous in Biology

2007-12-05 14:00:59 · 5 answers · asked by Anonymous in Weather

26 degrees here.....and we had snow today

2007-12-05 13:56:50 · 17 answers · asked by Sweet Judy 7 in Weather

please provide ur solutions. thxs

(a+?)^2= a^2 + ?a + 49

p.s- ^= exponent of the number

2007-12-05 13:55:39 · 3 answers · asked by Anonymous in Mathematics

2007-12-05 13:55:38 · 2 answers · asked by Anonymous in Botany

I have a quick question. We just finished boat races and I need to calcuate the bouyant force "exerted onto your boat by the water" as well as the "volume of water displaced by your boat."

We know that 1kg=1liter of water and 1 gallon=8.35lbs of water.

If you can please show me how (math-wise) I would appreciate it. I want to understand it too if I may ask, the answer is just a number but knowing how to calcuate it out is half the struggle. =)

2007-12-05 13:53:04 · 1 answers · asked by Greg J 2 in Physics

please help

2007-12-05 13:52:18 · 5 answers · asked by Anonymous in Mathematics

Please Help

2007-12-05 13:51:08 · 12 answers · asked by Anonymous in Mathematics

or has nobody been able to rpove it yet and its just one of those things that is accepted because nobody has disrproved it? Plz Help!

2007-12-05 13:44:14 · 1 answers · asked by In Testimony Whereof 3 in Mathematics

A right triangle has one angel that is 60 degree.The side adjacent to the 60 degree angle has the length of 7 in.How long is the opposite side?

2007-12-05 13:39:27 · 6 answers · asked by High_Sun 2 in Mathematics

How Apollo’s speed was controlled for its safe landing of on lunar surface. As there is no atmosphere and hence can’t be landed like a chopper.
Again its take off speed is very low and should be decreases because of moon’s gravity until another rocket fired in opposite direction for thrust. And I notice from the video there was nothing left at bottom of Apollo for the next thrust. So why Apollo did not decelerate by the moon’s gravity after certain height.
And how did Apollo was accelerated after take off as acceleration is the rate of change of velocity which can only be possible in empty space by firing rocket from time to time.
A thrust of 3500 lbs was used for LM take off on lunar surface . How did the design engineers calculate the final design speed on the basis of 3500 lbs thrust and moon’s gravity at rendezvoused with CSM in lunar orbit. Or what was its final design speed at the rendezvoused with CSM in lunar orbit.

2007-12-05 13:36:55 · 2 answers · asked by ? 3 in Astronomy & Space

A 0.1964 g sample of quinine (c6H4O2) is burned in a bomb calorimeter that has a heat capacity of 1.56 kj/K. The termperature of the colorimeter increases by 3.2k Calculate the heat of combustion of quinine per gram and per mole.

Please help me, i'm clueless!

2007-12-05 13:36:27 · 2 answers · asked by bb 4 in Chemistry