A 1-L sample contains 20 g of casein (C8H12O3N2). If 18 g of bacteria cell tissue (C5H7NO2) is synthesized per 50 g of casein consumed, determine the amount of oxygen required to complete the oxidation of casein to end products and cell tissue. The end products of the oxidation are carbon dioxide (CO2), ammonia (NH3), and water. Assume that nitrogen not incorporated in cell-tissue production will be converted to ammonia.