pls answer a & b, thank you

Required information [The following information applies to the questions displayed below.] The following are the transactions for the month of July. Required: a. Calculate cost of goods available for sale and ending inventory under weighted average cost. Assume a periodic inventory system used. b. Calculate sales, cost of goods sold, and gross profit, under weighted average cost. Assume a periodic inventory system is used. Complete this question by entering your answers in the tabs below. Complete this question by entering your answers in the tabs below. Calculate cost of goods available for sale and ending inventory under weighted average cost, Assume a periodic inventory system is used. (Round "Cost per Unit" to 2 decimal places and your final answers to nearest whole dollar amount.) Complete this question by entering your answers in the tabs below. Calculate sales, cost of goods sold, and gross profit, under weighted average cost. Assume a periodic inventory system is used. (Round "Cost per Unit" to 2 decimal places and your final answers to the nearest whole dollar amount.)