On January 7, 2005, Aaron Corporation acquired machinery at a cost of $1,200,000. Aaron adopted the sum-of-the-years-digits method of depreciation for this machine and had been recording depreciation over an estimated life of five years, with no residual value. At the beginning of 2007, a decision was made to change to the straight-line method of depreciation for this machine. Assuming a 30% tax rate, the cumulative effect of this accounting change, net of tax, is a. $112,000 b. $160,000 c. $168,000 d. $240,000