A tank with a capacity of 500 gal originally contains 200 gal of water with 100 lb of salt in solution. Water containing a salt
concentration of 1 lb/gal enters the tank at a rate of 3 gal/min, and the mixture is allowed to flow out of the tank at the rate of 2 gal/min. (a) Find the amount of salt in the tank at any time prior to the instant in which the tank begins to overflow.
(b) Find the amount of salt in the tank at the instant in which the tank begins to overflow.
