A machine with a cost of $75,096 has an estimated residual value of $4,450 and an estimated life of 6 years or 14,267 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 3,930 hours? Do not round your intermediate calculations. a.$20,686.01 b.$11,774.33 c.$23,548.67 d.$19,460.21