On May 1,2022 , X. Benedict Farms purchases a new milk separating machine at a cost of $18,000. The machine is estimated to have a 5 -year useful life, and a $2,400 salvage value at the end of its useful life. If X. Benedict Farms uses double-declining balance, what is the net book value of the milk separating machine as of December 31, 2022? (Round your answer to the nearest dollar.) (Numbers only. Do not use dollar signs, commas or decimals.)