Calculate the net present value (NPV) for the following 20-year projects. Comment on the acceptability of each. Assume that the firm has an opportunity cost of 14%. a. Initial investment is $10,000; cash inflows are $2,000 per year. b. Initial investment is $25,000; cash inflows are $3,000 per year. c. Initial investment is $30,000; cash inflows are $5,000 per year