1. An amount of R25 000 is invested at an interest rate of 11% per annum compounded half-yearly forn years. Find the value of n if at the end of this period the investment has accumulated to R58 890.
2. R2 000 is invested at 10% per annum compounded half-yearly. After three months, the interest rate changes to 12% per annum compounded monthly. Find the value of the investment after two years.