Explanation:
plan A
40 x 12 = 480 + 50 = 530
plan B
80 x 6 = 480 + 100 =580
plan c
60 x 12 = 720 no down payment
plan d
100 x 6 = 600 no down payment
so the highest finance charge will be plan c although it doesn't have down payment but the $60 charge every month for 12 months will estimate you the amount of $720