12. the following items are back to cement company for 2020: inventory 2019= 1,900,000, net sales=20,350,000, tax= 750,000 , EBT= 4,750,000, retain earning= 1000,000, paid in capital= 11,300,000, profit for preferred stocks= 25% ,A/R 2020= 630,000, preferred stocks = 5000,000, capital surplus= 50,000, gross profit = 7,000,000, inventory 2020= 2,100,000, based on this items solve the following: (61) 1- Average storage period and explain the result? (4 points) 2- calculate ROE ratio? (2 points) 3- What profit margin ratio measures in general? (2 points) (Non-anonymous question o)* (8 Points)