hello i need help plz , can someone explain me how we calculate the numbers in red plzzz

EXERCISE 2009 2010 2011 Sales E290,000 E360,000 (410,000 Sales Returns 6,000 13,000 10,000 Net Sales 284,000 347,000 400,000 Beginning Inventory 20,000 32,000 37,000** Ending Inventory 32,000* 37,000 34,000 Purchases 247,000 260,000 298,000 Purchase Returns and Allowances 5,000 8,000 10,000 Transportation-in 8,000 9,000 12,000 Cost of Goods Sold 238,000 256,000 303,000 Gross Profit on Sales 46,000 91,000 97,000