Hill Manufacturing uses departmental cost driver rates to apply manufacturing overhead costs to products. Manufacturing overhead costs are applied on the basis of machine-hours in the Machining Department and on the basis of direct labor-hours in the Assembly Department. At the beginning of 20X5, the following estimates were provided for the coming year: Machining Assembly Direct labor-hours 10,000 dlh 90,000 dlh Machine-hours 100,000 mh 5,000 mh Direct labor cost $ 80,000 $720,000 Manufacturing overhead costs $250,000 $360,000 The accounting records of the company show the following data for Job #846: Machining Assembly Direct labor-hours 50 dlh 120 dlh Machine-hours 170 mh 10 mh Direct material cost $2,700 $1,600 Direct labor cost $ 400 $ 900 Required: a. Compute the manufacturing overhead allocation rate for each department. b. Compute the total cost of Job #846. c. Provide possible reasons why Hill Manufacturing uses two different cost allocation rates.