Bricker Enterprises purchased a machine for $100,000 on October 1, 2018. The estimated service life is ten years with a $10,000 residual value. Bricker records partial-year depreciation based on the number of months in service.
Depreciation expense for the year ended December 31, 2018, using straight-line depreciation, is:

a) $1,500. b) $7,500. c) $2,250. d) $2,500.