The total revenue, in dollars, as a function of x, the number of units sold, is given as R(x) = 240x-0.5x2 (a) Use the function to complete the following sentences. Round to the nearest cent, as necessary. When 134 units are sold the total revenue is $ and the average revenue is $ per unit. When 398 units are sold the total revenue is $ and the average revenue is $ per unit. (b) Find the number of units that must be sold in order to maximize revenue. To maximize revenue, units must be produced and sold. The maximum possible revenue is $