a wood products company has decided to purchase new equipment for $139,805 with a trade-in of its old equipment. the old equipment has a BV on $10,000 at the time of the trade-in. the new equipment will be kept for 10 years before being sold. its estimated SV at the time is expected to be $5,000. using MACRS (GDS) recovery period, the depreciation charge permissible at year 6 is equal to