Question #1 - I spent $85.36 at Wegmans and charged it on my credit card. The card charges a commission of 45 cents plus 1 1/2%. How much does Wegmans get from my credit card company as payment?

Question #2 - I have the choice of two credit cards: Bank A: 12% interest rate, $60 annual fee Bank B: 18% interest rate, no annual fee How much, at least, would I need to keep as an average balance to prefer Bank A?