A stirred-tank blending process with a constant liquid holdup of 2m3 is used to blend two streams whose densities are both approximately 900kg/m3. The density does not change during mixing: (a) Assume that the process has been operating for a long period of time with flow rates of w1=500kg/min and w2=200kg/min, and feed compositions (mass fractions) of x1=0.4 and x2=0.75. What is the steadystate value of x ? (b) Suppose that w1 changes suddenly from 500 to 400kg/min and remains at the new value. Determine an expression for x(t) and plot it. (c) Repeat part (b) for the case where w2 (instead of w1 ) changes suddenly from 200 to 100kg/min and remains there. (d) Repeat part (c) for the case where x1 suddenly changes from 0.4 to 0.6 (in addition to the change in w2 )