Vincent had these daily balances on his credit card for his last billing period. He did not

Question:

Vincent had these daily balances on his credit card for his last billing period. He did not pay the card in full the previous month, so he will have to pay a finance charge. The APR is 19.2%.
Nine days @ $778.12
Eight days @ $1,876.00
Four days @ $2,112.50
Ten days @ $1,544.31
a. What is the average daily balance?
b. What is the finance charge?