Calculate the rate of return earned over the unspecified time period for each of the investments shown below:

Investment A: Cash flow during period: -$800 Beginning-of-period value: $1,100 End-of-period value: $100

Investment B: Cash flow during period: $15,000 Beginning-of-period value: $120,000 End-of-period value: $118,000

Investment C: Cash flow during period: $7,000 Beginning-of-period value: $45,000 End-of-period value: $48,000

Investment D: Cash flow during period: $80 Beginning-of-period value: $600 End-of-period value: $500

Investment E: Cash flow during period: $1,500 Beginning-of-period value: $12,500 End-of-period value: $12,400