Ruby Systems Corporation is estimating activity costs associated with producing disk drives, tapes drives, and wire drives. The indirect labor can be traced to four separate activity pools. The budgeted activity cost and activity base information, along with the estimated activity-base information is provided below. Procurement Scheduling Materials handling Product development Production Activity Cost $ 360,000 240,000 480,000 720,000 1,420,000 Activity Base Number of purchase orders Number of production orders Number of moves Number of engineering changes Machine hours Number Machine of Number of Engineering Changes Number of Purchase Orders 4,000 2,000 12,000 Number of Production Orders 300 150 800 10 Number of Units 2,000 4,000 2,500 Moves 1,400 600 4,000 Disk drives Tape drives Wire drives Hours 2,000 8,000 10,000 25 Determine the activity rate for production per machine hour. $20 $192 O $71 $80