R. Puff Company bought equipment for $105,000 on 1/1/16. The company estimated the useful life to be 10 years with a salvage value of $5,000, and straight-line depreciation method. On 1/1/18, the company decides the equipment's total useful life should be 7 years and salvage value is now $3,000. What is the revised depreciation expense per year? a. $16,400 b. $17,000 c. $12,143 d. $11,714