Redwood Corp. uses the units-of-production method to depreciate its machinery. Redwood purchased a machine on January 1st of the current year for $60,000. They estimate to sell the machinery at the end of its 10-year useful life for $10,000. Redwood estimates 100,000 total units can be produced on the machine. During the current year, 12,000 units are produced. What is the depreciation expense for the current year-end? $12,000 O $14,400 $6,000 O $6,500 $6,500.