1. Use the cash flow given below and a MARR = 12% to find the following:

Year	0	1	2	3	4	5
Net Cash Flow, $	+160,000	-32,000	-20,000	-70,000	-700	-8,000

a. Determine the number of possible rate of return values in the net cash flow series using the two sign tests.

b. Find the rate of return values with excel using interest between -30 and 130% and plot your results

c. Determine the external rate of return, using the modified rate of return approach with an investment rate 5% and a borrowing rate of 7%. Solve problem using excel.