A big tank initially contains 1000 L of a salt-water solution, which has a concentration of 0.02 kg of salt per liter. Brine (a solution of salt in water) containing 0.03 kg of salt per liter of water pours into the tank at 15 L/min. Assume the solution in the tank is kept well-mixed and drains from the tank at 15 L/min. Let y be the amount of salt in the tank at time t. Answering the following questions: a) (1pt) How much salt is in the tank initially? (i.e. it is the value of y(0) to be used later) b) (1pt) How many liters of solution are in the tank (i.e. volume of the tank) at any given time? c) (2pts) What is the rate at which salt is entering into the tank? d) (2pts) What is the rate at which salt is leaving the tank? e) (7pts) How much salt is in the tank after t minutes? f) (3pts) How much salt in the tank after 10 minutes?