To translate the train station at the same time one heading east west the westbound train travels at 75 mph the eastbound train travels at 95 mph how long will it take them to transfer be 306 miles apart

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?