Posson Corporation uses a job-order costing system with a single plantwide predetermined overhead rate based on machine-hours. The company based its predetermined overhead rate for the current year on 20,000 machine-hours, total fixed manufacturing overhead cost of $130,000, and a variable manufacturing overhead rate of $3.00 per machine-hour. Job K789, which was for 10 units of a custom product, was recently completed. The job cost sheet for the job contained the following data: a. Calculate the predetermined overhead rate for the year. b. Calculate the amount of overhead applied to Job K789. c. Calculate the total job cost for Job K789