On January 2 2017, Motors Inc. purchased an engine with a cost of $55,000. At the time, it was expected to last 5 years, with a residual valuevalue of $3,000. Three years later, on January 2, 2020 a new part was added to the engine, to increase its productivity. The new part has a cost of $27,000. Motors Inc. revised theit estimates to extend the expected useful life of the engine to 7 years, and the estimated residual value to $2,000. The revised amortization expense staring January 2020, would be:

A.

$10,400

B.

$12,200

C.

$23,800

D.

$31,200