A store manager calculates his store's monthly utility expenses using two expense rates r1 for the dollar cost per hour the store was open during the month and r2 for the dollar cost per hour the store was not open during the month. During November, which has 30 days, the store was open 8 hours a day, except one day when it was open for 15 hours for a special sale. Which of the following expressions should the manager use to calculate the store's utility expenses, in dollars for November ?

A store manager calculates his store's monthly utility expenses using

1.	A store manager calculates his store's monthly utility expenses using two expense rates r1 for the dollar cost per hour the store was open during the month and r2 for the dollar cost per hour the store was not open during the month. During November, which has 30 days, the store was open 8 hours a day, except one day when it was open for 15 hours for a special sale. Which of the following expressions should the manager use to calculate the store's utility expenses, in dollars for November ?
Answer» A store manager calculates his store's monthly utility expenses using two expense rates $r_{1}$ for the dollar cost per hour the store was open during the month and $r_{2}$ for the dollar cost per hour the store was not open during the month. During November, which has 30 days, the store was open 8 hours a day, except one day when it was open for 15 hours for a special sale. Which of the following expressions should the manager use to calculate the store's utility expenses, in dollars for November ?