Shawn purchases a retirement annuity that will pay him $1,000 at the end of every six months for the first nine years and $300 at the end of every month for the next six years. The annuity earns interest at a rate of 2.8% compounded quarterly. a. What was the purchase price of the annuity? Round to the nearest cent b. How much interest did Shawn receive from the annuity? Round to the nearest cent