I want to create a function.

Here's the Equation:

"Radius(in) X Radius(in) X 3.1416 X Height(in) X .0005787 X .803564 X 56 / 2000 = Tons"

The Radius I want to use cell "A1" and the Height cell "A2" and put the Answer in cell "A3". I have no clue so here is what I thought would work, I was wrong

"=QUOTIENT(=product(A1*A1*3.1416*A2*.0005787*.8035 64*56)/2000)"

Are there any suggestions? To make this true, what do I need to Change?

Thanks