请求这道题的算法：An investor wishes to have an amount of $4000 on ma

请求这道题的算法：An investor wishes to have an amount of $4000 on maturity in 5 years time
(I) if he invest his money at a simple interest rate of 12% per annum how much money should he invested now in order to achieve his aim?
(II) if he invest his money at a compound interest rate of 12% p.a.compounded monthly.how much money should he invest now in order to achieve his aim?