Gladstone Company tracks the number of units purchased and sold throughout each accounting period but applies its inventory costing method at the end of each period, as if it uses a periodic inventory system. Assume its accounting records provided the following information at the end of the annual accounting period, December $31.$

Transactions Units Unit Cost

Beginning inventory, January $13,200$ $ $45$

Transactions during the year:

a$.$ Purchase, January $304,55055$

b$.$ Sale, March $14($$$100$ each$)(2,850)$

c$.$ Purchase, May $13,25075$

d$.$ Sale, August $31($$$100$ each$)(3,300)$

Assuming that for Specific identification method $($item $1$d$)$ the March $14$ sale was selected two$-$fifths from the beginning inventory and three$-$fifths from the purchase of January $30.$

Required:

Compute the amount of goods available for sale, ending inventory, and cost of goods sold at December $31$ under each of the following inventory costing methods:

a$.$ Last$-$in$,$ first$-$out.

b$.$ Weighted average cost.

c$.$ First$-$in$,$ first$-$out.

d$.$ Specific identification, assuming that the March $14$ sale was selected two$-$fifths from the beginning inventory and three$-$fifths from the purchase of January $30.$ Assume that the sale of August $31$ was selected from the remainder of the beginning inventory, with the balance from the purchase of May $1.$

$2-$a$.$ Of the four methods, which will result in the highest gross profit?

$2-$b$.$ Of the four methods, which will result in the lowest income taxes?