Most manufacturing firms use a predetermined overhead rate (POHR). What is meant by the term predetermined overhead rate? How is it calculated and how is it used? Why do companies use predetermined overhead rates rather than actual manufacturing overhead costs? What factors should be considered in selecting an allocation base to be used in computing a predetermined overhead rate? Demonstrate your understanding by creating an example that includes the calculation of a POHR and the assignment of overhead to a job. Your response should contain at least 100 words, demonstrating that you understand the concept of predetermined overhead and its use