Answer the following independent questions: $($Round answers using average cost formula to $2$ decimal places, e$.$g$.15\mathrm{.}25.)$

$($a$)$ Assume that the company uses the FIFO cost formula. The cost of goods sold for the Jan. $21$ sale was $

$($b$)$ Assume that the company uses the average cost formula. The cost of goods sold for the Jan. $21$ sale was $

$($c$)$ Assume that the company uses the average cost formula. The value of the inventory after the Nov. $15$ sale was $

$($d$)$ Assume that the company uses the FIFO cost formula. The value of the inventory after the Oct. $20$ purchase is $