The price p (in dollars) and the demand x for a brand of running shoes are related by the equation
x=4,000-40p
(A) Express the price p in terms of the demand x, and find the domain of this function.
(B) Find the revenue R(x) from the sale of x pairs of running shoes. What is the domain of R?
(C) Find the marginal revenue at a production level of 1,600 pairs and interpret the results.
(D) Find the marginal revenue at a production level of 2,500 pairs, and interpret the results.