On January 1, 2010, Landon Excavation Company purchased a new bulldozer for $120,000. The equipment had an estimated useful life of 10 years and an estimated residual value of $10,000. On January 1, 2012, Landon determined that the bulldozer would have a total useful life of only 8 years instead of 10 years with no change in residual value. Landon uses straight-line depreciation. Compute depreciation expense on this bulldozer for 2010, 2011, and 2012.