Telecom uses activity-based costing to allocate all manufacturing conversion costs. Telecom produces cellular telephones; each phone has $30 of direct materials, includes 10 parts and requires 6 hours of machine time. Additional information follows: Activity Materials handling Machining Assembling Packaging Allocation Base Number of parts Machine hours Number of parts Number of finished units Cost Allocation Rate $4.50 per part $5.00 per machine hour $4.00 per part $2.00 per finished unit What is the cost of machining per phone? CE O A. $40 O B. $12 OC. $30 OD. $45