(1 point) A tank is filled with 1000 liters of pure water. Brinecontaining 0.05 kg of salt per liter enters the tank at 6 litersper minute. Another brine solution containing 0.07 kg of salt perliter enters the tank at 9 liters per minute. The contents of thetank are kept thoroughly mixed and the drains from the tank at 15liters per minute. A. Determine the differential equation whichdescribes this system. Let S(t) denote the number of kg of salt inthe tank after t minutes.
A) dS/dt = ?
B) Solve the differential equation for S(t).
