PLEASE HELP Ruby has a choice between three savings accounts. Savings account A has an APR of 3.9742% compounded monthly, savings account B has an APR of 3.9886% compounded quarterly, and savings account C has an APR of 3.9998% compounded semiannually. Ruby wants to choose the savings account with the highest APY.
Part I: If r is a savings account's APR and n is the number of compounding periods per year, what expression gives the savings account's APY?
Part II: What is the APY of savings account A to four decimal places?
Part III: What is the APY of savings account B to four decimal places?
Part IV: What is the APY of savings account C to four decimal places?
Part V: Which savings account offers the highest APY?