The monthly revenue R achieved by selling x wristwatches is figured to be R(x) = 75x-0.2x. The monthly cost C of selling x wristwatches is C(x) = 26x + 1650. (a) How many wristwatches must the firm sell to maximize revenue? What is the maximum revenue? (b) Profit is given as P(x) = R(x) - C(x). What is the profit function? (c) How many wristwatches must the firm sell to maximize profit? What is the maximum profit? (a) The firm must sell wristwatches to maximize revenue. (Round to the nearest integer as needed.) The maximum revenue is $ . (Round to two decimal places as needed.) (b) The profit function is P(x) = (Type an expression using x as the variable.) (c) The firm must sell wristwatches to maximize profit. (Round to the nearest integer as needed.) The maximum profit is $ (Round to two decimal places as needed.)