Cindy is buying a car from Robert for $4,500. Robert has agreed to accept a down payment of $500 and 16 consecutive monthly payments of $250 from Cindy to pay the car off. In agreement, Cindy writes up the following contract: “I agree to pay Robert a down payment of $500 in addition to 16 payments of $225 in exchange for this car.” Robert reads the contract and hands it back to Cindy without signing it. Which of the following is not a change Robert should ask Cindy to make to the contract? a. Cindy needs to change the monthly payment amount to $250 as agreed. b. Cindy needs to include the word “monthly” to describe the frequency of her payment. c. Cindy needs to change the number of payments to 17 to include the down payment. d. Cindy needs to include Robert’s last name and her full name.