Cox Inc. acquired a machine for $800,000 on January 1, 2019. The machine has a salvage value of $20,000 and a 5-year useful life. Cox expects the machine to run for 15,000 machine hours. The machine was actually used for 4,200 hours in 2019 and 3,450 hours in 2020.

What amount would Cox record as depreciation expense at December 31, 2020, if the double-declining-balance method were used?

a.$187,200

b.$195,200

c.$312,000

d.$192,000