1. compute the target volume in units to achieve a pre-tax profit of $ 86, 000 given a selling price of $18.00, variable costs of $ 4.00 and fixed costs of $ 74,000. 2. compute the pay-back period given an investment of $ 190,000 and even cash flows of $ 30,000 per year. 3. compute the pay-back period given an investment of $ 247,000 and cash flow inflows of $ 73,000, 63,000, 64,000 and 52,000. annual cumulative year 0 year 1 year 2 year 3 year 4