For the system methane(1)/ethane(2)/propane(3) as a gas, estimate f^1,f^2,f^3,^1,^2, and ^3 at t=100C,P=35 bar, y1=0.21, and y2=0.43 : (a) Through application of Eq. (10.64). (b) Assuming that the mixture is an ideal solution