Final answer:
The depreciation expense for 2020 using the straight-line method is $7,500.
Step-by-step explanation:
The annual depreciation expense for 2020 using the straight-line depreciation method can be calculated by subtracting the revised estimated residual value from the initial cost of the van and dividing it by the remaining useful life. In this case, the initial cost of the van is $15,000 and the revised estimated residual value is $0. Since the van was purchased on January 1, 2017, it has already been used for 3 years out of its total useful life of 5 years. Therefore, the remaining useful life is 5 - 3 = 2 years.
Depreciation expense = (Initial cost - Revised residual value) / Remaining useful life
= ($15,000 - $0) / 2
= $15,000 / 2
= $7,500
Therefore, the depreciation expense for 2020 using the straight-line depreciation method is $7,500.