A machine with a cost of $74,804 has an estimated residual value of $5,983 and an estimated life of 7 years or 17,696 hours. It is to be depreciated by the units-of-activity method. What is the amount of depreciation for the second full year, during which the machine was used 4,336 hours? Do not round your intermediate calculations. a.$19,663.14 b.$18,329.01 c.$9,831.57 d.$16,863.01