The company uses the perpetual inventory system for recording its cost of sales. The inventories and purchases for the month of Decem are as follows:

December $1,$ Beginning inventory: Quantity is $100$ units, cost per unit is $$1\mathrm{.}00.$ December $3,$ Purchase: Quantity is $200$ units, cost per unit is $$1\mathrm{.}30.$ December $7,$ Sales: Sales is $220$ units. December $9,$ Purchases: Quantity is $200$ units, cost per unit is $$1\mathrm{.}80.$ December $14,$ Sales: Sales is $280$ units. December $18,$ Purchases: Quantity is $300$ units, cost per unit is $$2\mathrm{.}00.$ December $21,$ Sales: Sales is $200$ units. December $30,$ Purchases: Quantity is $100$ units, cost per unit is $$2\mathrm{.}20.$

During the month, units were sold for $$3\mathrm{.}50$ per unit.

For the purpose of this question, please ignore GST$.$

Calculate the Cost of Goods available for Sale for December?

Calculate the Cost of Sales for $14$ December using the FIFO method?

Calculate the Cost of Sales for $14$ December using the LIFO method?

Calculate the Cost of Sales for $14$ December using the weighted average cost method?

Using the weighted average cost method, calculate the dollar amount$($$$)$ assigned to the inventory on hand on $31$ December and the cost of sales for the month December?