Part $1$: Compute the inventory at May $31$ on each of the following bases. Assume that perpetual inventory records are kept in units only. Carry unit costs to the nearest cent. Assume costs are not computed for each withdrawal:

Compute:

$1.$ First$-$in$,$ first$-$out

$2.$ Last$-$in$,$ first out

$3.$ Average cost $($i$.$e$.,$ weighted average method$)$