College Math prblem.. PLEASE HELP!!?

[LucyLu]

The problem: The Film Frisbee Company is working on a new type of Frisbee to sell on the toy market. They have studied all aspects and determined that the cost of producing "x" number of Frisbees would be represented by the equation C(x)=100,000-108x+0.045x^2

1.) What would be the value of "x" that would provide the minimum cost of production? What is the minimum cost?

They also determined that the revenue for selling "x" units would be best if they used the equation R(x)=x^2+2,400x+1,000
2.) What would be the value of "x" that would provide the maximum revenue of the production? What is the Maximum revenue?
3.) What would be the maximum Profit that the company could expect?

* I have to show work*
PLEASE help even if it is a little!!

[Jon D]

This sounds like calculus, and here to find a maximumor minimum you have to use the derivative. Then take C'(x) and plug in 0 for C'(x), that will give you the critical points (can be maximums or minimums). Then use the second derivative, C"(x) to find if it is concave up or down. If C"(x) is negative, the function is concave down and so is a maximum, if C"(x) is positive it's concave up and so a minimum.
I don't have the time to do it out, hope this helps.