a company uses a predetermined overhead rate based on machine hours to apply manufacturing overhead to jobs. the company has provided the following estimated cost for next year: direct materials 10,000 direct labour 30,000 sales commissions 40,000 salary of production supervisor 20,000 indirect materials 4000 advertising expense 8000 rent on factory equipment 10000 the company estimates that 5000 direct labour hours and 10000 machine hours will be worked during the year. the predetermined overhead rate per hour will be