A company's average cost per unit when x units are produced is defined to be Average cost = Total cost x . Suppose a company's average costs are given by Average cost = 5000 x + 75 + 0.5x. (a) Write the expression that gives the company's total costs. (b) Find the average cost per item of 100 items. Round answer to the nearest penny. $ (c) Find the total cost of 100 items. Round answer to the nearest penny. $