Doris Davis borrowed $8,200 on March 5 for 90 days at 8 3/4%. After 32 days, Doris made a payment on the loan of $2,700. On the 65th day, she made another payment of $2,500. What is her final payment if you use the U.S. Rule with ordinary interest?
a) $4,667.50
b) $3,907.50
c) $4,290.00
d) $3,450.00