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when is the predetermined manufacturing overhead rate computed
A pre-determined overhead rate is the rate used to apply manufacturing overhead to work-in-process inventory. The pre-determined overhead rate is calculated before the period begins.
how is the pre-determined overhead rate computed
The first step of the pre-determined overhead rate is to estimate the amount of the activity base that will be required to support operations in the upcoming period.

Question: what is the second step
Self-contained rewrite: what is the second step of the pre-determined overhead rate after estimating the amount of the activity base that will be required to support operations in the upcoming period