1)Present value How much money should be invested in an account that earn 8% Interest, Compounded semiannually in order to have $18,000 in 7 years?

Answer : $10,683.29

2) Loan To help pay your college expense you borrow $8000 and agree to repay the loan at the end of 5 year of 7% Interest, Compounded quarterly

A) What is the maturity value of the loan ? Answer : $11,318.23

B) How much interest are you paying on the loan? Anwer : $3318.23

I have answer but I forget How I did the work. Can you show the work?