Shown below is activity for one of the products of Denver Office Equipment: Compute the January 31 ending inventory and cost of goods sold for January, assuming Denver uses FIFO and a perpetual inventory system. Now assume Denver uses LIFO and a perpetual inventory system. Compute the January 31 ending inventory and cost of goods sold for January. Assume Denver uses LIFO and a perpetual inventory system and was able to anticipate the upcoming sale of 750 when they made the additional purchase of inventory on the 20^th. Also assume Denver would like to minimize COGS for January. What amount of inventory would Denver have purchased on the 20th, and what would the resulting COGS and ending inventory be for January