Jenny’s backyard it cost $76.00 per square yard to build the deck is 9 yards wide and 11 yards long how much did it cost to build the deck

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?