3. The management of Demetrius Corporation would like to better understand the behavior of the company's warranty costs. Management believes that warranty cost is a mixed cost that depends on the number of product returns. Those costs are listed below for several recent months. Required: a. Estimate the variable cost per product return and the fixed cost per month using the high-low method. b. If product returns are estimated to be 31 in November, what will be the estimated total cost of warranties for November? Product Returns Warranty Cost March 32 $3,648 April 37 $4,074 May 43 $4,760 June 41 $4,330 July August September October 34 30 $3,756 48 $4,782 35 $3,932 33 $3,823