XYZ Company has three main overhead activities: machining, assembly, and finishing. The total estimated overhead costs for each activity are $150,000,$100,000, and $75,000, respectively. Overhead is applied on the basis of machine hours for machining and direct labor hours for both assembly and finishing. If direct labor hours are projected to be 50,000 for the year and machine hours are expected to be 25,000 for the year, what is the activity rate for machining? a. $3 per machine hour b. $3 per direct labor hour c. $6 per machine hour d. $6 per direct labor hour