1) Capital is interest-bearing for 4 years and 3 months with an annual interest rate of 7% and gives a final value of 500. Find the initial capital.

2) Capital 100 is interest-bearing with an annual interest rate of 4% and gives a final value of 120. Find the time in which this capital became 120.

3) Capital 100 is interest-bearing for 5 years and gives a final value of 125. Find the annual interest rate.