A factory machine was purchased for R.0.90,000 on January 1, 2011. It was estimated that it would have a R.O.ooo residual value at the end of its 5-year useful life. It was also estimated that the machine would be run 40,000 hours in the 5 years. The company ran the machine for 4,000 actual hours in 2011. If the company uses the units-of-activity method of depreciation, the amount of depreciation expense for 2011 would be Select one: a. R.O.9,000. b.R.O.7,200. O c.R.O.14,400. 0 d.R.O.18,000