Calculating Manufacturing Overhead Rates Windsor Company, accumulated the following data for 2017: In the Milling department, grooves are cut into aluminum and steel rods using computer-controlled equipment. In the Finishing department, the rods are individually cleaned and polished. a. Calculate the plantwide manufacturing overhead rate using machine hours as the allocation base. \$ per machine hour b. Calculate the plantwide manufacturing overhead rate using direct labor hours as the allocation base. $ per direct labor hour c. Calculate department overhead rates using machine hours in Milling and direct labor hours in Finishing as the allocation bases. \$ per Milling Dept. machine hour $ per Finishing Dept. direct labor hour d. Calculate department overhead rates using direct labor hours in Milling and machine hours in Finishing as the allocation bases. $ per Milling Dept. direct labor hour $ per Finishing Dept. machine hour