Marlow is comparing the prices of two truck rental companies. company a charges $3 per hour and an additional $75 as service charges. company b charges $2 per hour and an additional $85 as service charges. part a: write an equation to represent each company's total charges for renting a truck for a certain number of hours. for both equations (one for company a and one for company b), define the variable used. part b: which company would charge less for renting a truck for 5 hours? justify your answer. part c: how much money is saved by using the services of company a instead of company b to rent a truck for 3 hours?