What is the volume of this rectangular prism

Me. i can't figure out this question. give an explanation too. .

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

Evaluate the function , when d = {9, 15, 30}. r = {5, 7, 12} r = {6, 10, 15} r = {6, 10, 20} r = {5, 12, 20}