A large tank contains500liters of a salt solution which has a concentration of0.45kilograms per liter. A salt solution which has a concentration of0.6kilograms per liter is added to the solution at a rate of 50 liters per minute. At the same time, the solution drains from the tank at 55 liters per minute.

1.) Set up a differential equation describing the rate of change of the amount of saltSwith respect to time t:

2.) When t=0,what is S?