I just need help doing this tab, I have no idea what to put.

a How many units did we sell? 4,1001000+4000900 Between FIFO and LIFO, which method is preferable in terms of maximizing income? Which ones did we sell? FIFO \begin{tabular}{|l|r|r|r|} \hline Beginning Inv & 1,000 & 35 & 35,000 \\ \hline First Purchase & 4,000 & 38 & 152,000 \\ \hline \multicolumn{1}{l|}{ second Purchase } & & & \\ \cline { 1 - 2 } & & & \end{tabular} Between FIFO and LIFO, which method is preferable in terms of minimizing income taxes? How many units remain? \begin{tabular}{|l|r|r|r|} \hline Beginning Inv & 1,000 & 35 & 35,000 \\ \hline Ending Inv & & & \\ \hline \end{tabular} \begin{tabular}{|l|l|l|l|} \hline b How many units did we sell? & 4,100 & 100035+310038 & 152,800 \\ \hline \end{tabular} Which ones did we sell? \begin{tabular}{|l|l|l|r|} \hline Second Purchase & & & 4,100 \\ \hline First Purchase & & & 4,000 \\ \hline COGS & & & \\ \hline \end{tabular} How many units remain? 9003834,200 Second Purchase LIFO c What is the average cost of one unit? \begin{tabular}{|l|l|r|r|} \hline \multicolumn{1}{c|}{ Units } & \multicolumn{2}{c|}{ Unit Cost } \\ \hline Beginning Inv & & 35 & \\ \hline Purchased & & 38 & \\ \hline & & & \\ \cline { 2 - 5 } & & & \\ \hline \hline \end{tabular} Average Cost How many units did we sell? COGS How many units remain? Ending Inventory \begin{tabular}{|r|r|} & 37.40 \\ \hline 153,350 & \\ \hline & \\ \hline 33,660 \\ \hline \end{tabular}