A portable concrete test instrument used in construction for evaluating and profiling concrete surfaces (MACRSGDS 5-year property class) is purchased in December by a calendar-year taxpayer for \($22,000.\) The instrument will be used for 6 years and will be worth \($2,000\) at that time.

a. Calculate the depreciation deduction for years 1, 3, and 6.

b. If the instrument is sold in year 4, determine the depreciation deduction for years 1, 3, and 4.