Chapter 2.6, Problem 99E

A company that sells radios has yearly fixed costs of $600.00. It costs the company $45 to produce each radio Each radio will sell for $65. The company’s costs and revenue are modeled by the following functions, where x represents the number of radios produced and sold:

$\begin{array}{cc}c(x)=600,000+45x& \text{This function molels the company's costs}\\ R(x)=65x.& \text{This function models the company's revenue}.\end{array}$

Find and interpret $(R-C)(20,000),(R-C)(30,000),and(R-C)(40,000)$.