Nick Santiago purchased a used for $35,000. Before the tractor could be used, it required new tires, which costs $2,200, and an overhaul, which cost $2,800. Its first tank of fuel cost $150. The tractor is expected to last six years and have a residual value of $4,000. Determine the cost and depreciable cost of the tractor and calculate the first year’s depreciation under the straight-line method.