The table below shows how much joe earns y after working x hours

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Charlie is at an amusement park that has 18 different rides. each ride costs $1.75. the function c(r) = 1.75r represents the total amount of money that charlie will spend if he goes on r rides, but he never goes on the same one more than once. what domain and range are reasonable for the function?

Ineed here’s a picture of the question