Assume that a retailer$$s beginning inventory and purchases of a popular item during January included $(1)430$ units at $$8\mathrm{.}30$ in beginning inventory on January $1,(2)580$ units at $$9\mathrm{.}30$ purchased on January $8,$ and $(3)880$ units at $$10\mathrm{.}30$ purchased on January $29.$ The company sold $480$ units on January $12$ and $680$ units on January $30.$

Required:

Calculate the cost of goods sold for the month of January under $($a$)$ FIFO $($periodic calculation$),($b$)$ FIFO $($perpetual calculation$),$ and $($c$)$ LIFO $($periodic calculation$).$

Which cost flow assumption and calculation approach would you recommend to management in order to save taxes?