Find the maximum profit and the number of units that must be produced and sold in order to yield the maximum profit. Assume that revenue, R(x), and cost, C(x), of producing x units are in dollars. R(x) = 60x - 0.1x , C(x) = 6x + 15 In order to yield the maximum profit of $ , units must be produced and sold. (Simplify your answers. Round to the nearest cent as needed.)