www0 a solution with a saltA very large tank initially contains 100L of pure water. Starting at time tconcentration of 0.8kg/L is added at a rate of 5L/min. The solution is kept thoroughly mixed and isdrained from the tank at a rate of 3L/min. Answer the following questions.1. Let y(t) be the amount of salt (in kilograms) in the tank after t minutes. What differential equation doesy satisfy? Use the variable y for y(t).Answer (in kilograms per minute):dydtm3y100 + 2t2. How much salt is in the tank after 40 minutes?Answer (in kilograms):