16. On May 1, a company sold some machinery to another company. The two companies entered into an installment sales contract at a predetermined interest rate. The contract required five equal annual payments with the first payment due on May 1, the date of sale. What time value of money concept is appropriate for this situation? (a) Future value of a single amount of $1 for five periods. (b) Present value of an ordinary annuity of $1 for five periods. (c) Future value of an annuity due of $1 for five periods. (d) Present value of an annuity due of $1 for five periods