Compton Ltd purchased equipment on 1 January 2013, at a cost of $60,000. The equipment was originally estimated to have a salvage value of $5,000 and an estimated life of 10 years. Depreciation has been recorded through 31 December 2016, using the straight-line method. On 1 January 2017, the estimated residual value was revised to $6,000 and the useful life was revised to a total of 8 years. What is the depreciation expense for 2017?

a.$7,500.

b.$6,750.

c.$6,875.

d.$8,000.

e.$9,375.