Science & Mathematics - 8 July 2007

A Coin is unique in that the outer edge is gold while the inside is silver. Assuming both sides of the coin are identical, and a line tangent to the inner circle is 23 mm from edge to edge of the coin, and excluding the edge of the coin in the calculation, what is the surface area of gold on the coin, in square millimetres?




How do I solve this?

2007-07-08 05:38:12 · 4 answers · asked by Anonymous in Mathematics

2007-07-08 05:35:06 · 8 answers · asked by aimeelou1984 1 in Biology

i realize that the human population is much larger then it was say, 2000 yrs. ago. does that mean the earth weighs more? i know there's no weight in space, but just in theory. also, the astronauts don't count, they'll just mess it up.

2007-07-08 05:34:24 · 17 answers · asked by Ashley W 1 in Astronomy & Space

(Hypothetical speaking ofcourse), Who would you sell this idea to and for what price? What are the repercussions of such discovery on world economy. Oil, Gas, Transport, MiddleEast?

2007-07-08 05:31:15 · 4 answers · asked by Anonymous in Physics

Factor: y2 - 16

2007-07-08 05:30:04 · 8 answers · asked by andy s 2 in Mathematics

2007-07-08 05:28:59 · 5 answers · asked by Anonymous in Engineering

Solve for 'a' using the elimination method:

3a + 4b = 2
4a - 3b = -14

2007-07-08 05:28:45 · 4 answers · asked by andy s 2 in Mathematics

what does thier work envolve,& who needs one?

2007-07-08 05:28:06 · 2 answers · asked by katieville502 2 in Engineering

i suck at this

5a2 + 3a - 2

2007-07-08 05:19:39 · 6 answers · asked by andy s 2 in Mathematics

Determine whether the trinomial below is a difference of squares, a perfect square trinomial, just factorable, or nonfactorable.
x2 - 10x + 25

A. difference of squares
B. perfect square trinomial
C. nonfactorable
D. factorable

2007-07-08 05:19:31 · 3 answers · asked by how's it going 1 in Mathematics

if u like math try it if you want to figure it out type me somthing! thanx!

2007-07-08 05:10:25 · 9 answers · asked by alice b 1 in Mathematics

It happened today. The temperature dropped 8ºF and the humidity that sticked to the windows got frozen. Inside, the temperature was like 68, but it still got frozen!

...I wonder if you people can guess where I'm living.

2007-07-08 05:08:20 · 4 answers · asked by Philidor 5 in Weather

Explain why would you expect that H neutzn for HBr reacting with NaOH solution and H neutzn for HNO3 reacting with KHO solution would be identical.

2007-07-08 05:07:17 · 2 answers · asked by jasonanthonybau 1 in Chemistry

2007-07-08 05:06:35 · 8 answers · asked by camalbalz 1 in Other - Science

The accepted h neutzn of hydrobomic acid HBr reacting with NaaOh solution and of HNO3 reacting with potaassium hydroxide KOH solutions are identical

2007-07-08 05:04:38 · 2 answers · asked by jasonanthonybau 1 in Chemistry

how do I find the surface area of a shape swept out by the curve x^2 rotated through 360 degrees about the x axis. Between x=1 and x=2. Imagine it like a lampshade on its side. I want the surface area of it.

This is not a homework, I was just messing about and realised that I couldn't do it and now it is bugging me.

I know that I need to find the length of the curve by Integrating sqrt(4x^2+1)dx. So my answer is found by Integrating 2Pi*x^2*sqrt(4x^2+1)dx using the limits x=1 and x=2.

Now for this I have used trigonometric substitution and end up needing to integate
(Pi/4)[(tanT)^2] [(secT)^3]dx

Note: theta=T

This is where I get stuck how do I integrate this? Have I gone about it the right way?

2007-07-08 05:02:52 · 6 answers · asked by eazylee369 4 in Mathematics

2007-07-08 04:56:07 · 10 answers · asked by Anonymous in Astronomy & Space

2007-07-08 04:55:11 · 3 answers · asked by Anonymous in Chemistry

Thank you!

2007-07-08 04:53:46 · 2 answers · asked by ? 1 in Mathematics

Long time ago when I was younger I would hear that the goverment has a time travel machine....could this be possible? Could they change things and we don't even notice? And is it even possible for anyone to time travel?

2007-07-08 04:49:17 · 6 answers · asked by Anonymous in Other - Science

2007-07-08 04:47:52 · 14 answers · asked by d@dz 5 in Mathematics

when their is the word ide at the end of an equation for example : Zinc Sulfide - does it refer to the sulfide or sulfate? what is the equation for that element?

2007-07-08 04:47:30 · 2 answers · asked by PETER Boy 2 in Chemistry

2007-07-08 04:45:51 · 2 answers · asked by david a 1 in Other - Science

me and my bf had an argument over it last night lol and he said "you dont know if its raining somewhere" but thats not true is it? i mean theres places that its absicaly always raining in , like the rainforests right? plz tell me lol ty

2007-07-08 04:42:49 · 9 answers · asked by Anonymous in Weather

superior vena cava, inferior vena cava, left and right brachiocephalic veins, left and right internal and external jugular veins, left and right subclavian veins, left and right axillary veins, left and right brachial veins, left and right renal veins, adrenolumbar vein either side, left and right femoral veins, left and right common iliac veins, left and right internal iliac veins, left and right external iliac veins, genital vein either side, gastrosplenic vein, coronary vein, intestinal vein, and hepatic portal vein.

2007-07-08 04:42:22 · 1 answers · asked by javi 4 in Biology

Hypothetically speaking, let's say in the year 2099 someone travels back in time to ancient Egypt around 2500 B.C. and accidentally leaves behind a unique item that was created in the year 2099. Years later, in 2010, archaeologists discover the item at some ancient ruins site and perform carbon dating on the odd object. What would the carbon dating tell the researchers about the item?

2007-07-08 04:39:42 · 4 answers · asked by Anonymous in Earth Sciences & Geology

I am going a little bit further than Everest Base Camp so would like to know how high mosquitoes fly on the mountain, what time of day they are most of a problem and any information about their existence at Everest Base Camp.

Any information would be greatly appreciated.

Many thanks.

2007-07-08 04:35:41 · 2 answers · asked by Caroline L 2 in Geography

2007-07-08 04:30:27 · 23 answers · asked by Anonymous in Mathematics

4x^2 - 29x + 7

(if it cannot be factored indicate if it is prime)

2007-07-08 04:30:20 · 4 answers · asked by D-pig 4 in Mathematics

how do I factor x^4+2x^2+9 and x^4+4x^2+16

THANKS!!!!

2007-07-08 04:28:58 · 4 answers · asked by Anonymous in Mathematics