please explain

Taveras Corporation is currently operating at 50% of its available manufacturing capacity. It uses a job-order costing system with a plantwide predetermined overhead rate based on machine-hours. At the beginning of the year, the company made the following estimates: Machine-hours required to support estimated production Fixed manufacturing overhead cost Variable manufacturing overhead cost per machine-hour 255,000 $ 5,100,000 $ 2.00 Required: 1. Compute the plantwide predetermined overhead rate. 2. During the year, Job P90 was started, completed, and sold to the customer for $4,300. The following information was available with respect to this job: Direct materials Direct labor cost Machine-hours used $ 1,978 $ 1,419 90 Compute the total manufacturing cost assigned to Job P90