The students in Ms. Bass’s class decide to order water bottles that advertise the walkathon. Bruno obtains two different quotes for the costs of the bottles. Fill It Up charges $4 per bottle. Bottles by Bob charges $25 plus $3 per bottle. a. Which variable is the independent variable? Which is the dependent variable? b. For each company, write an equation Bruno could use to calculate the cost for any number of bottles. c. For what number of water bottles is the cost the same for both companies? d. Which company do you think the class should buy water bottles from and why?