how do I get the gross profit for specific identification??

Greg's Bicycle Shop has the following transactions related to its top-selling Mongoose mountain bike for the month of March. Greg's Bicycle Shop uses a periodic inventory system. Cost per $250 270 Transactions Units Unit Total Cost March 1 Beginning Inventory March 5 Sale ($400 each) March 9 Purchase March 17 Sal($450 each) March 22 Purchase March 27 Sale ($475 each) March 30 urchase $ 5,000 2,700 2,800 2700 $ 13.200 15 300 Greg's Bicycle Shop has the following transactions related to its top-selling Mongoose mountain bike for the month of March. Greg's Bicycle Shop uses a periodic inventory system. Cost per $250 270 Transactions Units Unit Total Cost March 1 Beginning Inventory March 5 Sale ($400 each) March 9 Purchase March 17 Sal($450 each) March 22 Purchase March 27 Sale ($475 each) March 30 urchase $ 5,000 2,700 2,800 2700 $ 13.200 15 300