a.) A business produces 4,000 units per month which it sells at $20/unit. Costs include: $10,000 on raw materials, $15,000 in wages for operators and $10,000 in wages to sales people. If the business is just breaking even, what are its fixed costs?

b.) A firm sells 300,000 units per week. It charges $ 35 per unit, the average variable costs are $40, and the average costs are $55. In the short run, the firm should.

c.) A firm sets its price at $10.00 per unit. It has an average variable cost of $8.00 and an average fixed cost of $4.00 per unit. In the long run, this firm is.

d.) A firm's sunk costs are $100,000 and its marginal costs are $250 per unit. It produces 500,000 units and prices it at $400 per unit. How low can price go before the firm decides to shut down?

e.) If the annual interest rate is 10%, the net present value of receiving $550 in the next year is: