In September 2007, Democratic presidential candidate Hillary Rodham Clinton suggested that every child born in the United States should get a $5,000 "baby bond" from the government to help pay for future costs of college or buying a home. Assume this suggestion is accepted and the every baby born in America is given a $5,000 account at birth.
a). If the money is invested at an annual return of 10%, how much will the account have by the time that young person turns 18?
b). If the young person needs to get $40,000 from the account when he/she turns 18, at what interest rate should be money be invested?