Science & Mathematics - 24 August 2007

chalcopyrite, the principle ore of Copper (Cu) contains 34.63% Cu by mass. How many grams of Cu can be obtained from 9.83x10^3 kg of the ore?

2007-08-24 05:51:20 · 3 answers · asked by Anonymous in Chemistry

Magnesium hydroxide

Sulfuric acid

Chloric acid

Sodium hydroxide

2007-08-24 05:51:12 · 8 answers · asked by Anonymous in Chemistry

2007-08-24 05:49:06 · 7 answers · asked by Anonymous in Mathematics

How would you factor the following?

xˆ2 - 4x - 12????

2007-08-24 05:48:47 · 17 answers · asked by Anonymous in Mathematics

{2x + 4y = -1}
{3x + y = 1}

2007-08-24 05:43:30 · 7 answers · asked by Anonymous in Mathematics

2007-08-24 05:41:56 · 4 answers · asked by Anonymous in Earth Sciences & Geology

Show your work and expain if you can

Thanks

2007-08-24 05:41:49 · 5 answers · asked by Doug 1 in Mathematics

2007-08-24 05:41:44 · 3 answers · asked by Anonymous in Mathematics

Female silkworm moths attract males by emitting chemical signals that spread through the air. A male hundreds of meters away can detect these molecules and fly toward their source. The sensory organs responsible for this behavior are the comblike antennae on their heads. Each filament of an antenna is equipped with thousands of receptor cells that detect the sex attractant. Propose a hypothesis to account for the ability of the male moth to detect a specific molecule in the presence of many other molecules in the air.

2007-08-24 05:41:38 · 5 answers · asked by Anonymous in Biology

(f(a + h) - f (a)) / h?

Show work and describe if you can.

2007-08-24 05:39:34 · 5 answers · asked by Doug 1 in Mathematics

An AED 1000, 14% bond with semi-annual coupons redeemable at par on April 11, 2016 is purchased on October 11, 2004 to yield 9% semi-annual interest.

How many coupons are left on this bond?

The answer i got is 25
coz i multiplied: 12.5 *2 = 25 << the number of coupons..
what would the right answer be?

2007-08-24 05:30:49 · 3 answers · asked by Yuuji 1 in Mathematics

How would you factor this problem:

18x(to the third power) y + 12xy

2007-08-24 05:27:19 · 5 answers · asked by Anonymous in Mathematics

Is it moving in the positive or negative direction of x just then?

2007-08-24 05:26:33 · 2 answers · asked by Wonder 2 in Physics

51478963, 51478523, 50809268, 44907545, 52148317, and i'm not talking about length.

2007-08-24 05:25:25 · 3 answers · asked by bspain0 2 in Mathematics

The last problem in my summer math packet was made for a genius so if you r one please show me how to solve it. thanks

(3(n+1)!)/(5n!)

2007-08-24 05:22:34 · 3 answers · asked by adamb417 2 in Mathematics

I don't know how. I thought of increasing the positive charge in a very high and elevated area.

What do you think? Is that possible?

2007-08-24 05:11:56 · 7 answers · asked by Anonymous in Physics

2007-08-24 05:09:03 · 1 answers · asked by Anonymous in Physics

2007-08-24 05:00:27 · 7 answers · asked by stevenyoungers 1 in Physics

The projectile was fired from (90W, 0N) and landed on the opposite side of the Earth at (90E, 0E).

Curious amateur photographer located at (0E, 30N) noticed a bright object rising over the horizon, and made a picture of its trajectory.
He directed his camera horizotally due south, and let exposition continue until the object fell under horizon. The trace of the projectile on the film is

a) parabola
b) ellipse
c) hyperbola
d) impossible to predict


(ignore rotation of Earth)

2007-08-24 04:59:23 · 1 answers · asked by Alexander 6 in Physics

2007-08-24 04:57:34 · 8 answers · asked by chris l 1 in Zoology

There has always been a question in my mind when it come to wind generated energy. If for example there are a series of wind turbines across say Europe all placed in the various countries all positioned to catch the prevailing wind. That is the wind comes into contact will the first series of wind powered turbines and moves on to the next and so on into the various countries as it passes on its natural route. Will the wind be weaker when it meets the last series of wind turbines? Given that some of the energy of the wind has been used on those wind turbines which first in the line of the wind

Will the introduction of so called wind farms be a catalyst for climate change given that cloud formations are driven by the prevailing winds. If there is a reduction of wind speed it is possible that precipitation could occur in different location than it did before the introduction of wind farms. If the strength of the wind is reduced will it be diverted form its natural course.

2007-08-24 04:52:46 · 11 answers · asked by de_falla 2 in Weather

Latley I've been having trouble sleeping. What are some things that can help me sleep? What are some ways that I can help myself fall asleep?

2007-08-24 04:50:32 · 6 answers · asked by carrr 1 in Biology

Given Quadrilateral ABCD and the points A(-2, 6), B(4, 6), C(4, -3) and D(-2, -3). Use the distance formula to find the lengths of each side. Give the most specific name for this polygon. Show all your work.

2007-08-24 04:49:40 · 4 answers · asked by Anonymous in Mathematics

2007-08-24 04:47:48 · 3 answers · asked by abdach2000 1 in Engineering

i like cheese

2007-08-24 04:44:43 · 8 answers · asked by capiche77 1 in Mathematics

2007-08-24 04:44:06 · 5 answers · asked by micaela m 1 in Chemistry

How long do spiders live after laying there egg sack?
my sister has a rely cool pet wolf spider
thats been a pet all summer and it laid its egg sack
then like a week later it ran away yesterday
in the middle of the nite then cam back last nite
why wood it leave and then come back?
and wen she lade the egg sack it had 1 big egg in it and now
its multiplied in to a bunch of little eggs and its still multiplieng
do all spider egg sacks do that?
and how can you tel if the egg sack is fertile?

2007-08-24 04:43:34 · 2 answers · asked by quailchick1374444 2 in Zoology

http://i40.photobucket.com/albums/e215/xxs3xp1stolxx/Picture7.png

2007-08-24 04:40:05 · 1 answers · asked by ryan s 1 in Mathematics

A trapezoid has one pair of parallel sides.

Always

Sometimes

Never

2007-08-24 04:38:37 · 7 answers · asked by ryan s 1 in Mathematics

Given rectangle WXYZ. If WX = 10y - 4 and YZ = 13y - 7, find the value of y.

1

3

3.3

6

2007-08-24 04:36:05 · 1 answers · asked by Anonymous in Mathematics