3. The production manager has provided you with the following information for the months of September and October: September: Hours worked = 3,000, Average cost per hour = $8.50 October: Hours worked = 4,000, Average cost per hour = $7.90 Based on this information, what are the estimated fixed and variable cost per hour (respectively) for this production department? a. $7,200; $6.10 b. $9,600; $6.10 c. $13,300; $6.10 d. $23,700; $0.60 e. $29,200; $0.60