This question is from apex: economics with financial literacy: 7.5.3 quiz ( ! )

trina has a credit card that uses the adjusted balance method. for the first 10 days of one of her 30-day billing cycles, her balance was $780, she then made a purchase for %170, so her balance jumped to $950, and it remained that amount for the next 10 days. trina then made a payment of $210, so her balance for the last 10 days of the billing cycle was $740. if her credit card's apr is 17%, which of these expressions could be used to calculate the amount trina was charged in interest for the billing cycle?

(answers: )

a. (0.17/365 (dot) 30) (10 (dot) $780 + 10 (dot) $950 + 10 (dot) $210/30)

b. (0.17/365 (dot) 30) ($570)

c. (0.17/365 (dot) 30) ($780)

d.(0.17/365 (dot) 30) (10 (dot) $780 + 10 (dot) $950 + 10 (dot) $740/30)