Example 5: Given f (x) = 2x+1 and g (x) = x2 -x-3, find each of the following: a. (f . 8) (x) b. (go f ) (x) c. (go f ) (-1) Example 6: A company that sells radios has yearly fixed costs of $600,000. 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: C(x) =600,000 + 45x R (x) = 65x Find and interpret (R-C) (20,000 ) and (R-C) (30,000)