Final answer:
The depreciation expense for 2018, using the units-of-production method, would be approximately $8,067.
Step-by-step explanation:
The amount of depreciation expense for 2018, using the units-of-production method, can be calculated by first determining the depreciation rate per hour. The depreciation rate is calculated by subtracting the estimated residual value from the cost of the equipment and dividing it by the estimated total hours of use. In this case, the depreciation rate per hour would be ($110,000 - $20,000) / 30,000 = $3.33 per hour.
To calculate the depreciation expense for 2018, we can multiply the depreciation rate per hour by the number of hours the equipment was used in that year. In this case, the equipment was used for 2,200 hours, so the depreciation expense for 2018 would be $3.33 x 2,200 = $7,326. Therefore, option b, $8,067, is the closest approximation to the amount of depreciation expense for 2018.