12.10 LO2-5 Gina Ltd uses a predetermined overhead rate in applying overheads to product costs, using direct labour costs for cost centre A and machine hours for cost centre B. The following details the forecasts prepared for 2017 on which the overhead rates are to be based: A Direct labour costs $90,000 $45,000 Production overheads $130,000 $160,000 Machine hours 1,200 3,500 Nuforma is one of the products manufactured by Gina in a process that involves the two cost centres A and B. The following data relate to the resources used to make the product during 2017: A $7,600 $8,900 Direct materials Direct labour $5,700 $4,300 Machine hours 63 45 (a) Calculate the predetermined overhead rate for cost centres A and B. (b) Assuming that product Nuforma consists of 4,000 units, what is its unit cost