Fill in depreciation expense in year 3 under each depreciation method when residual value is $30,000 and useful life is 3 years:

Depreciation method:
Straight-line
Units-of-Output
Double-declining

2. Fill in the book value at the end of year 1 under each depreciation method when residual value is $36,000 and useful life is 4 years:

Depreciation method:
Straight-line
Units-of-Output
Double-declining	Please help me solve it and how do you does methds. Accounting class