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An company bought a telecommunication equipment for 280,000. Other expenses including installation amount to 40,000. The equipment is set to have a 12 years with the salvage value at the end of life of 30,000. Determine the depreciation charge during the 4th year, depreciation up to the 7th year and the book value at the end of the 10th years by

(a) declining balance method

(b) straight-line method

(c) SYD method

(d) double declining balance method

(e) sinking fund method with i=20%.