Problem 3. Find an equation of the curve that pasM's through the point (O, 2) and whose slope and (x, y) is :r/y. Problem d. A tank contains 1000 L of brine with 15 kg of dissolved salt. Pure water enters the tank at a rate of 10 L/rnin. The solution is kept thoroughly mixed and drains from Che Cank at the same rate. How much salt is in the tank (a) after t minutes and (b) after 20 minutes. Problem 5. (a): Solve the differential equation (b): Find a solution to the equation from part (a) subject co the initial condition = l. Hint: You'll need to apply L'llopital's rule.