Orange Company purchased equipment on July 1 for $28,500 and decided to depreciate the equipment on the straight-line method over its useful life of five years. Assuming the equipment's salvage value is $4,500, the amount of monthly depreciation expense Nelson should recognize is:

a. $2,400
b. $ 200
c. $4800
d. $400
e. $ 450

Answer: d. $400