Beginning inventory, purchases, and sales for WCS$12$ are as follows:

Oct. $1$ Inventory $320$ units at $$13$

Oct $13$ Sale $170$ units

Oct $22$ Purchase $350$ units at $$16$

Oct $29$ Sale $400$ units

A$.$ Assuming a perpetual inventory system and using the weighted average method, determine the weighted average unit cost after the October $22$ purchase. Round your answer to two decimal places.

B$.$ Assuming a perpetual inventory system and using the weighted average method, determine the cost of goods sold on October $29.$ Round your "average unit cost" to two decimal places.

C$.$ Assuming a perpetual inventory system and using the weighted average method, determine the inventory on October $31.$ Round your "average unit cost" to two decimal places.