Fill in the lettered blanks in the following table: Amount of investment Economic life in years Investment A Investment B Investment C $80,000 (a) $20,000 10 5 Annual cash flow $10,000 (b) $2,500 Payback period in years (c) 4 (d) Present value of cash flows (e) $66,000 (f) Net present value $5,500 $6,000 ($1,000)