Final answer:
Sandy's total annual cost for her credit card is $72.65.
Step-by-step explanation:
To calculate the total annual cost of Sandy's credit card, we need to consider the membership fee, the balance transfer fee, and the finance charges she paid throughout the year.
- Membership fee: $15.
- Balance transfer fee: 5% of $823.46 = $41.17.
- Finance charges paid in February, May, July, and September: $3.56 + $5.82 + $4.92 + $2.18 = $16.48.
To find the total annual cost, we add up these amounts: $15 + $41.17 + $16.48 = $72.65.
Therefore, the total annual cost of Sandy's credit card is $72.65.