Bargain Rental Car offers rental cars in an off-airport location near a major tourist destination in California. Management would like to better understand the variable and fixed portions of its car washing costs. The company operates its own car wash facility in which each rental car that is returned is thoroughly cleaned before being released for rental to another customer. Management believes that the variable portion of its car washing costs relates to the number of rental returns. Accordingly, the following data have been compiled:

Month	Rental Returns		Car Wash Costs
January	2,500		$	11,600
February	2,500		$	13,400
March	2,800		$	12,400
April	3,100		$	15,200
May	3,700		$	16,800
June	5,200		$	24,500
July	5,600		$	22,800
August	5,600		$	23,700
September	4,800		$	23,400
October	4,200		$	22,900
November	2,300		$	11,300
December	3,000		$	16,300

2. Using least-squares regression, estimate the variable cost per rental return and the monthly fixed cost incurred to wash cars.