I need help solving 3 and 4 please

At 12/31/17, the end of Windy Company's first year of business, inventory was $8, 300 and $6, 700 at cost and at market, respectively. Prepare the entry at 12/31/17 necessary to implement the LCNRV procedure assuming Windy uses a contra account for its balance sheet. At 12/31/18, inventory was $7, 250 and $6, 600 at cost and at market, respectively. Prepare the entry at 12/31/18 necessary to implement the LCNRV