All $640,000 of the sales will be collectible. however, collection costs will be 5 percent of sales, and production and selling costs will be 75 percent of sales. the cost to carry inventory will be 6 percent of inventory. depreciation expense on plant and equipment will be 5 percent of plant and equipment. the tax rate is 30 percent. a. compute the investments in accounts receivable, inventory, and plant and equipment based on the turnover ratios. add the three together.