$30 per machine hour
Explanation:
The firm's predetermined overhead rate for 2019 is computed as;
= Budgeted factory overhead / Budgeted machine hours
Given that;
Budgeted factory overhead = $1,290,000
Budgeted machine hours = 43,000 hours
Predetermined over head rate = $1,290,000 / 43,000 = $30 per machine hour