ANSWER and EXPLANATION
Let the cost of renting the truck be C.
Let the number of miles be m.
Let the number of days be d.
The cost of renting the truck is $25 per day plus $0.32 per mile.
This implies that the cost of renting the truck is:
(a) The cost of renting a truck for one day and 480 miles is found by substituting 1 and 480 for d and m respectively:
(b) The cost of renting a truck for one day and 520 miles is:
(c) The cost of renting a truck for two days and 600 miles is:
(d) The cost of renting a truck for three days and 975 miles is: