how do i get ending history, cost of goods sold, gross profit for FIFO, LIFO, Weighted average cost

i am lost in how to get these answer

FIFO First-in. Firet-at \begin{tabular}{c|l|r|lr|rrr} & COGS - LIFO & 10 & $ & 50 & $ & 500 \\ \hline 3-Mar & Purchase & 200 & $ & 55 & $ & 11,000 \\ \hline 10-Mar & Purchase & 40 & $ & 60 & $ & 2,400 \\ \hline 30-Mar & Purchase & 250 & & & $ & 13,900 \end{tabular} ENDING INVENTORY - LIFO \begin{tabular}{l|l|r|rr|rr} 1-Mar & Beginning inventory & 100 & $ & 40 & $ & 4,000 \\ \hline 3-Mar & Purchase & 50 & $ & 50 & $ & 2,500 \\ \hline & & 150 & & $ & 6,500 \end{tabular} GROSS PROFIT - LIFO \begin{tabular}{l|l|rr} Total Sales & $ & 21,800 \\ \hline Less: COGS & $ & (13,900) \\ \hline Gross Profit & $ & 7,900 \end{tabular} WEIGHTED AVERAGE COST Total dollar amount of goods available for sale 400$20.400$51.00 Average cost per unit