Copy House Ltd produces two types of computer printers, a laser model and an inkjet model, which pass through two production departments, Production and Assembly. The following data relate to the year just ended: Budget information: Budgeted overhead Expected activity in direct labour hours) Expected activity (in machine hours) Production Assembly $270 000 $135 000 22 500 90 000 45 000 12 375 Laser Inkjet 11 250 112 500 $90 000 $675 000 Actual Information: Units produced Prime costs Direct labour hours used: Production Assembly Machine hours used: Production Assembly 1 500 30 000 21 000 72 000 15 000 1 500 30 000 12 000 Note: Actual overhead costs for the year were $450,000. Required: Show all your workings i. Calculate the predetermined plantwide overhead rate based on direct labour hours. (4 marks) Calculate the per unit cost of the laser and inkjet printers, based on a plantwide overhead rate assuming that direct labour hours is the cost driver. (6 marks) Calculate the predetermined departmental overhead rates, assuming that machine hours is the cost driver in production and direct labour hours is the cost driver in assembly (4 marks) Calculate the cost per units of the laser and inkjet printers, based on the departmental overhead rates. (6 marks) Estimate the amount of underapplied or overapplied overhead using: a. Plantwide overhead rate. (2 marks) b. Departmental overhead rates. (3 marks) vi. Which approach is best for Copy House Ltd: a plantwide overhead rate or departmental overhead rates? Why? (3 marks) iv