How is this question done?? Milk chocolate is being produced in a 300 litre tank, which initially contains 100 litres of milk. The following things then occur simultaneously: 1. Liquid cocoa (made up of equal parts cocoa solids and cocoa butter, both in liquid form) is added at a rate of 6 litres per minute. 2. Milk is added at a rate of 3 litres per minute. The well-stirred mixture leaves the tank via a tube, at a rate of 6 litres per minute. The differential equation for dx/dt + 6x / (100 + 3t) = 3 ......Therefore...... x(t) = (9t^3 + 900t^2 + 30,000t) / (3t + 100)^2 Find the time in minutes (t) for the mixture to be 25% Cocoa solids.