For production of lactic acid (C3H6O3), lactose (C12H22O11) is used as a substrate and ammonia (NH3) assists. The stoichiometry for the overall lactic acid synthesis is: 25C12H22O11+7H2O+6NH3>6C5H7O2N+90C3H6O3 The molecular weights of lactic acid, lactose, and ammonia are 90.08, 342.3, and 17.03 g/mol, respectively. Batch fermentation of lactic acid production for scientific experiments is carried out in a 100-liter tank. Initially, the tank is filled with nutrient medium containing 50g/1 lactose and 4g/1 ammonia, and the reaction is stopped when the lactose concentration is 4.5g/1. When results from the fermentation process were analyzed, it was found that 22% of the lactose had been used for growth, 67% for cell maintenance activities (such as membrane transport and macromolecule turnover), and only 11% for lactic acid production. Determine: (a) What is the limiting substrate if H2O is provided in excess? (b) What is the total mass of lactose used for growth? (c) What is the amount of lactic acid produced (in moles and grams)? (d) What is the final concentration of ammonia