Science & Mathematics - 16 December 2007

2007-12-16 09:08:54 · 5 answers · asked by star_prince0 2 in Astronomy & Space

2007-12-16 09:08:14 · 3 answers · asked by star_prince0 2 in Earth Sciences & Geology

Whats the chemical formula for the compound

cobalt (III) oxide

AND

tin (II) phosphate

2007-12-16 09:07:12 · 2 answers · asked by CT 3 in Chemistry

2007-12-16 09:06:32 · 3 answers · asked by star_prince0 2 in Geography

If the detergent requires using 0.63 kg detergent per load of laundry, determine what percentage (by mass) of the detergent should be sodium carbonate in order to completely precipitate all of the calcium and magnesium ions in an average load of laundry water.
Sodium carbonate is often added to laundry detergents to soften hard water and make the detergent more effective. Suppose that a particular detergent mixture is designed to soften hard water that is 3.3×10^−3 in Ca+2 and 1.0×10^-3 M in Mg 2+ and that the average capacity of a washing machine is 20.0 gallons of water.

2007-12-16 09:05:30 · 2 answers · asked by Anonymous in Chemistry

i dont know how to do this problem here it is:

a bicycle maker sold 300 bicycles last year at a profit of $300 each. The maker wants to increase the profit margin this year, but predicts that each $20 increase profit will reduce the number of bicycles sold by ten. How many $20 increases in profit can the maker add in and expect to make a total profit of $100,000?

if someone can solve it step by step and give explanations it would be more than appreciated

2007-12-16 09:04:37 · 2 answers · asked by Anonymous in Mathematics

A box contains nickels, dimes and pennies worth $8.40. The number of dimes is six less than twice the number of pennies and there is an equal number of dimes and nickels. How many nickels are there in the box? Type in your numerical answer only; do not type any letters or words with your answer.


Ok I got that...

d + p + n = 8.40
n = d


From there I dont know how to find the value of nckels...

2007-12-16 09:04:15 · 2 answers · asked by Tiffany R 1 in Mathematics

2007-12-16 09:03:05 · 19 answers · asked by Celeritas 5 in Zoology

smaller person.

2007-12-16 09:02:55 · 9 answers · asked by Anonymous in Physics

2007-12-16 09:01:25 · 1 answers · asked by Greg 2 in Biology

2007-12-16 09:01:08 · 9 answers · asked by rodneyallen2004 1 in Chemistry

The energy in tides is enormous, why is it not being harnessed? I know the rate of flow of water is slow, but it takes massive amounts of energy to move water - say into a bay - and then out again.

I would envision building a dam say 1km from shore - we have the technology - just. Then giant gates with turbines attached would generate almost continuous electricity.

Wind power always was a bad idea and is starting to die, as it deerves to. However tides are constant. Water is heavy. Ever built a small dam on a stream at a beach, and been amazed when you let the water out 30 minutes later? If you haven't, you should try it and see the energy.

This can hardly be an original thought, so is it being tried or is there a more fundamental problem? What am I missing?

2007-12-16 08:59:10 · 3 answers · asked by Anonymous in Physics

The mass of an average blueberry is 0.75g and the mass of an automobile is 2200 kg.

2007-12-16 08:58:45 · 2 answers · asked by Anonymous in Chemistry

1. solve x^(1/2) -6= -x^(1/4)

the answer is 16

2. find log3 (81)=?
logpie (1/pie cubed)
log1000 (10)

answers are 4 ,-3, 1/3

3. simplify completely

(x-6)/(x^2-4) - (x-1)/(2-x) - (x+1)/(x+2)

the answer is 3/(x+2)

Thanks for all help. God bless all and have a happy holidays!

2007-12-16 08:57:33 · 1 answers · asked by dreamz 4 in Mathematics

Suppose that the length of time between consecutive high tides is approximately 12.5 hours. According to the National Oceanic and Atmospheric administration, on Saturday, June 28, 1997, on a certain beach, high tide occurred at 4:38AM (4.6333 hours) and low tide occurred at 11:08AM (11.1333 hours). Water heights are measured as the amounts above or below the mean lower low water. The height of the water at high tide was 8.5 feet and the height of the water at low tide was -0.9 feet.

Find a sinusoidal function of the form y = Asin(omega x - phi) + B that fits the data

2007-12-16 08:57:14 · 1 answers · asked by Anonymous in Mathematics

2007-12-16 08:56:01 · 2 answers · asked by Wattsup! 3 in Physics

1. A person wants to make an rectangular enclosed play pen using 60 meters of fence. One of the sides is against the house (thus, not requiring any fencing). What are the dimensions of the play pen to get the maximum area?

2. A boat can go 12 mph in calm water. If the boat goes down a river 45 miles and back up the river 45 miles it takes him 8 hours. What is the current of the river?

2007-12-16 08:54:50 · 5 answers · asked by Anonymous in Mathematics

Im having trouble solving this:

Given an array a of integers and an integer x. The program SEARCH
searches for an occurrence of x in a. If x occurs in a, the result i is the
index of the occurrence. If x does not occur in a, the result i equals to
the size of the array.

2007-12-16 08:53:53 · 1 answers · asked by Anonymous in Mathematics

27. 2/*7*-*3* *-square root of
29. (3-2i)/(3+2i)
31. solve by completing the square: 4x^2-12x+7=0
32. Solve by using the quadratic formula: 9y^2+12y+5=0
33. Find the real values of k for which kx^2-6x+3=0 has two imaginary roots.

sorry it's a lot of problems to solve.. please solve the ones you can and include the work process too. thank you :)

2007-12-16 08:53:33 · 3 answers · asked by Anonymous in Mathematics

Consider the function f(x) = ex – kx, where k is a positive constant and x ≥ 0.

a. how do u Find all the critical points of f in terms of k.
b. how do u Find the anti-derivative F(x) satisfying F(0) = 3.

2007-12-16 08:52:49 · 1 answers · asked by Asiana 1 in Mathematics

First of all, evolutionists need to stop stating anything from their work as fact, because none of it is proven.
But my specific example that maybe one of you Darwin-suckers can help me with is this:
Why do they say that parrots or peacocks have their colorful plumage and have noisy calls because they evolved that way to attract mates. Yet, sparrows, grackles and other dull, boring birds get laid all the time, even without blue or orange feathers.
And conversely, why is it said that sparrows, grackles and otherh dull brownish birds have such colors to avoid prey. Meanwhile, these parrots who need flashy colors to get laid are defeating the purpose of all this fornication by being easy to spot by predators.
Pure nonsense.

2007-12-16 08:52:24 · 7 answers · asked by Anonymous in Biology

How low is the Freezer's temperature?

Is it 32 F? Could you explain this logically? I have to solve answer the quetion

At what temperature is the freezer kept? explain

2007-12-16 08:52:17 · 3 answers · asked by Hawk J 1 in Other - Science

Suppose in another habitable planet there are beings that are human-like, and there's no racism, no money, no rent, no war, everyone is nice and everything is free. Would you move to another planet to start your life?

What would mankind do if they arrived to the planet?

I am just curious about your opinion.

2007-12-16 08:52:17 · 9 answers · asked by caltam84 3 in Astronomy & Space

3y^3-2x^3-6x^2y+5y=0

I found dy/dx to be 6x^2+12xy/9y^2-6x^2+5, but if I set that to dy/dx to 0, I have 2 variables (x and y) to deal with. Any help would be great!

2007-12-16 08:52:02 · 2 answers · asked by ¿ /\/ 馬 ? 7 in Mathematics

Each machine in a certain factory can produce 50 units per hour. The setup cost is $80 per machine, and the operating cost is $5 per hour. How many machines should be used to produce 8000 units at the least possible cost?

thanks

2007-12-16 08:51:48 · 1 answers · asked by Jason 2 in Mathematics

A man float with a chair 193 miles with 105 heliums balloons (http://www.msnbc.msn.com/id/19694083/) Assuming that mars gravity is one third of earth ....What volume or balloon size is needed to airborn one kilo of instrument on Mars atmosphere

2007-12-16 08:51:41 · 3 answers · asked by fernando19562000 2 in Astronomy & Space

a simple answer for this question that i just cant seem to word would be helpful :)

2007-12-16 08:50:50 · 3 answers · asked by Anonymous in Chemistry

The question is:
Find the equation of the line that is perpendicular to 4x+3y=6 and that passes through the point (-1,-4).

The answer is y=3/4x-13/4, but i don't understand how to get that. Could anyone please explain this to me? Thank you very much!

2007-12-16 08:49:44 · 2 answers · asked by Anonymous in Mathematics

What is the first and second derivatives of f(x)= x/(x-1)^2?

I'm confused...do u have to use the chain rule?

2007-12-16 08:49:34 · 1 answers · asked by Asiana 1 in Mathematics

2007-12-16 08:49:17 · 8 answers · asked by crazinati91 1 in Chemistry