1. Under-allocated manufacturing overhead costs are always the result of which of the following situations? 2. what is the centrepiece of a job-costing system Black Company uses predetermined overhead rates to apply manufacturing overheads to jobs. The predetermined overhead rates are based on machine hours in Department A and direct labour cost in Department B. At the beginning of the year, the company made the following estimates: What predetermined overhead rates would be used in Departments A and B respectively?