A company has two departments, machining and assembly. The total overhead costs are $4,000,000 for the machining department and $2,000,000 for the assembly department. Projected total units are 500,000 machine hours (machining department) and 100,000 direct labor hours (assembly department). Compute the machining and assembly department's overhead rate. a. $20 per machine hour for the machining department and $8 per direct labor hour for the assembly department. b. $8 per machine hour for the machining department and $20 per direct labor hour for the assembly department. c. $40 per machine hour for the machining department and $4 per direct labor hour for the assembly department. d. $4 per machine hour for the machining department and $40 per direct labor hour for the assembly department. e. $20 per direct labor hour for the machining department and $8 per machine hour for the assembly department.