On the first day of the year, Firefall Company acquired equipment for use in operations at a cost of

$340,000. The equipment was expected to have a useful life of four years or 1,000 hours, and a residual value of $20,000. The equipment was used for 280 hours during the first year, 260 hours during the second year, 240 hours during the third year, and 220 hours during the fourth year.

Determine the annual depreciation expense in each year and the book value of the equipment at the end of each year under the:

1. straight-line method 2. units-of-activity method 3. double-declining-balance method