A machine with a cost of $72,106 fas an estimated residual value of $4,094 and an estimated lfe of 7 years or 18,765 hours. It is to be depredated by the units of activity method. What is the anount of depreciation for the second full year, during which the machine was used 4 , 778 hours? Do not round your intermediate calculations. a. 937174 b. 51843456 d. 117.119.96