Science & Mathematics - 16 January 2007

We got this question today in class as just trivia (first day of class) and I can't find it anywhere online --- What element is found in antibiotics and it also keeps away ticks?
Do any of you Chemists out there know what this is? Thanks for your help!
First person to answer with link that tells me what element is found in antibiotics gets the prize!

2007-01-16 12:28:49 · 2 answers · asked by shomaliatimalla 3 in Chemistry

2007-01-16 12:28:43 · 6 answers · asked by Eric Sun 1 in Mathematics

Just wondering if I figured this out right...Potassium (K) contains 19 valence electrons and Bromine (Br) contains 35, Oxygen (O) conains 8 and Carbon (C) would then contains 6..am I completely wrong? If I am could someone correct me? Thanks!

2007-01-16 12:28:39 · 9 answers · asked by Anonymous in Chemistry

(–2, –3) and (–4, 4)
of these points, which on is x1, x2, y1 and y2?

2007-01-16 12:28:16 · 5 answers · asked by Amanda H 2 in Mathematics

or just solve these?

P1V1 = P2V2

2007-01-16 12:28:13 · 6 answers · asked by Anonymous in Chemistry

Couldn't it be round or something?

http://www.universedaily.com

2007-01-16 12:27:42 · 7 answers · asked by Wayne S 1 in Mathematics

Couldn't it be round or something?

http://www.universedaily.com

2007-01-16 12:27:26 · 6 answers · asked by Wayne S 1 in Earth Sciences & Geology

Couldn't it be round or something?

http://www.universedaily.com

2007-01-16 12:27:12 · 3 answers · asked by Wayne S 1 in Physics

Couldn't it be round or something?

http://www.universedaily.com

2007-01-16 12:26:53 · 15 answers · asked by Wayne S 1 in Astronomy & Space

2007-01-16 12:26:50 · 2 answers · asked by mohamed a 1 in Physics

Pretend a person can walk only at a certain pace -- no faster, no slower. If you time her uninterrupted walk across a room of known length, you can calculate her walking speed. If, however, she stops momentarily along the way to greet others in the room, the extra time spent in her brief interactions gives an average speed across the room that is less than her walking speed. How is this like light passing through glass? In what way is it not?

2007-01-16 12:26:23 · 7 answers · asked by Anonymous in Physics

Volume of NaOH, mL; pH
0; 2.88
5; 4.15
10; 4.58
12.5; 4.76
15; 4.93
20; 5.36
24; 6.14
24.9; 7.15
25; 8.73
26; 11.29
30; 11.96

Just from this data, how can I find pH at the equivalence point, Ka, and pKa (actually just need to know how to find one of the two Ka or pKa and I can get the other)

please

2007-01-16 12:25:55 · 2 answers · asked by Anonymous in Chemistry

The height, in feet, of a missile is given by H= 1600t-16t^2 and the t is the time in seconds.

A) What is the maximum height reached by the missile??
B) What is the time it reaches the maximum height??
C) What is the time when the missile hits the ground??

Explain the answers!!
Thax!

2007-01-16 12:25:40 · 3 answers · asked by Anonymous in Mathematics

When light encounters a material, it can build up vibration in the electrons of certain atoms that may be intense enough to last over a long period of time. Will the energy of these vibrations tend to be absorbed and turned into heat, or absorbed and reemitted as light?
(a)absorbed and converted into light
(b)absorbed and turned into heat

In what direction is the polarization of the glare that reflects from a horizontal surface?
(a)horizontal
(b)neither; light is blocked
(c)vertical

You can get a sunburn on a sunny and on an overcast day. But you cannot get a sunburn if you are behind glass. Explain.

How long does light take to travel from the sun to Earth?
min
From the star Alpha Centauri to Earth?
yr

Why would you expect the speed of light to be slightly less in the atmosphere than in a vacuum?

2007-01-16 12:25:32 · 2 answers · asked by Anonymous in Physics

i love looking at pictures of cosmos. i just wonder if the colors you see on say the science channel are correct. in other words, if you were to travel to distant nebuli, would you see these beautiful colors, or would you need to look through special lenses or take pictures on infrared or any other special type of film?

2007-01-16 12:24:30 · 11 answers · asked by Louiegirl_Chicago 5 in Astronomy & Space

Three letters.

2007-01-16 12:24:01 · 3 answers · asked by horacebeardenjr 1 in Zoology

2007-01-16 12:23:36 · 5 answers · asked by Anonymous in Earth Sciences & Geology

Four letters.

2007-01-16 12:22:51 · 4 answers · asked by horacebeardenjr 1 in Zoology

A surveyor has been hired by a resort developer to determine if a mountain is high enough to develop with a ski lift. The surveyor approaches the problem as follows:

In the valley below he sets up a transit at point K and sights an angle of elevation to a prominent rock R at the top to be 48degrees. He moves the transit to a second point M and measures the angle of elevation to R to be 45.3 degrees.

A. If distance KM is 100m across level ground, and the line MK when extended meets a perpendicular from R, determine the height of the mountain.
B. Find the length of the ski run from R to K.

I have no idea how to get this..could you please help me understand the problem?

2007-01-16 12:22:48 · 3 answers · asked by shitheadjulie1 1 in Mathematics

9y^3+57y^2+60y

thanks

2007-01-16 12:22:36 · 3 answers · asked by pirsimone 1 in Mathematics

I hope some1 on here is really, really smart.

I totally fell asleep in class and I'm totally confused on what we are supposed to do concerning quadratics. These are my following questions:
*How on earth do you find the axis of symmetry on a calculator(I've got one of them fancy TI ones from school)??
*what is the vertex of a parable(pronounced parabla i think)?
*number one says this: y= 2x^2 + 12x-11

I want to at least be able to solve number one!! I usually don't do this(ask a homework question on Yahoo Answers), but I am desperate! I'm not the type to fall asleep in class. Today was a bad day. Can anyone help me??

2007-01-16 12:21:24 · 3 answers · asked by Anonymous in Mathematics

with no gap between them tho

http://img393.imageshack.us/img393/6320/whatdoyouseedm4.jpg

2007-01-16 12:20:52 · 6 answers · asked by honiez_of_uk 2 in Other - Science

Three letters.

2007-01-16 12:20:26 · 2 answers · asked by horacebeardenjr 1 in Zoology

I really have a hard time in my math class, and my profesor explains things very quickly, so either I have to pay attention and not take notes or not takes notes and pay attention. So, it is a catch 22. I just don't want the answer, I would like to know exactly how you go about doing these types of problems.

Here is the problem.... 3a^-2 divided by c^-3

the ^ means to the power of.. how would I solve this step by step, and is there an easier way to do this problem?

2007-01-16 12:20:14 · 6 answers · asked by Anonymous in Mathematics

2007-01-16 12:18:55 · 8 answers · asked by Anonymous in Biology

2007-01-16 12:15:56 · 13 answers · asked by tjcsonofallnations 3 in Astronomy & Space

You invest $200. After on year, the total of the investment is $208.80. Solve the formula A=P+Prt where A is the total of the investment, P is the principal (amount invested), r is the annuall simple interest rate, and t is the time in years, for r. Find the annual simple interest rate. How much money would your investment have if you leave it in for another two years with the same interest rate? Explain your answer.

2007-01-16 12:15:02 · 3 answers · asked by Nocturne 3 in Mathematics

x = p - q dividided by pq.

How can i find what q equals?

2007-01-16 12:14:48 · 5 answers · asked by Hatman 1 in Mathematics

Mr. Green grows several varieties of tomatoes in a rectangular garden. He used fencing to divide the garden into 36 squares that are 1m by 1m. He also puts fencing around the perimeter of the garden. What is the smallest length of fencing that Mr. Green Needs???

Please when answering, give me all the steps you have used to complete the problem. THANKS

2007-01-16 12:14:04 · 1 answers · asked by Mike 2 in Mathematics

2007-01-16 12:13:50 · 8 answers · asked by Anonymous in Chemistry