Plantwide versus departmental overhead rates; actual and normal costing: manufacturer LO 7.3, 7.4, 7.7 Noteperfect Ltd manufactures sheet music stands in two separate departments, cutting and welding. The following data relate to the year just ended: Cutting department Welding department Total plant Budgeted manufacturing overhead $120 000 $240 000 $360 000 Actual manufacturing overhead $108 000 $216 000 $324 000 Budgeted machine hours 24 000 96 000 120 000 Actual machine hours 27 000 90 000 117 000 Budgeted direct labour hours 30 000 15 000 45 000 Actual direct labour hours 29 400 11 700 41 100 One of Noteperfects major products, the A Frame, has the following production requirements: Product: A Frame Cutting department Welding department Total plant Machine hours 2.5 4.0 6.5 Direct labour hours 4.0 1.0 5.0 Required: 1. Calculate the manufacturing overhead cost of the A Frame using: (a) a predetermined plantwide rate based on direct labour hours (b) a predetermined plantwide rate based on machine hours (c) predetermined departmental rates based on direct labour hours for the cutting department and on machine hours for the welding department. Which of these three estimates of overhead cost is likely to be the most accurate? Explain. 2. Calculate the manufacturing overhead cost of the A Frame, using an actual costing system and departmental overhead rates based on labour hours for cutting and on machine hours for welding. Explain why cost drivers must be used with actual costing as well as with normal costing. 3. Which estimate of overhead costs is likely to be more accuratethat based on predetermined departmental rates or that based on actual departmental rates? Explain