Molly earned $160 for walking her neighbors dog. if she walked the dog five hours each week for eight weeks how much did she make per hour?

I'm at a bookstore with $\$35$ in my pocket and a $20\%$-off coupon. what is the cost of the most expensive book i can buy with my money and the coupon? (assume that there are books of every possible price in the bookstore. it's a large bookstore! )