Guys help me!

1. What is the domain and range? Help plsss!

Charlie is a car salesman he earns $800 plus a 9% commission on all of her sales for the week if charlie receive the payment for $1960 this week how much where is total sales

John bought 5 lemons and used 2 of them for a salad how much did he use for.a salad . he used % of the lemons.

Solve - pv + 40 < 65 for v solve 7w - 3r = 15 for r