Answer:
$12,000
Step-by-step explanation:
total value to be depreciated over 6 years = machine's cost - salvage value = $40,000 - $4,000 = $36,000
the unit of depreciation we are going to use is machine hours:
depreciation cost per machine hour = $36,000 / 24,000 total machine hours = $1.50 per machine hour
depreciation expense for 20x1 = 8,000 hours x $1.5 per machine hour = $12,000