Answer:
$20,000.
Step-by-step explanation:
Step 1 : Applied overheads
Applied overheads = $143,350 - $18,220 = $125,130
Step 2 : Overhead rate
Overhead rate = $125,130 / 9,700 = $12.90
The estimated manufacturing overhead at the beginning of the year used in the predetermined overhead rate must have been $20,000.