Pressure in the vapor space 3rd effect: 4.2 psia; pressure in the vapor space 4th effect: 0.92 psia; liquor from 3rd effect: 20% solute, 170F; liquor from 4th effect: 40% solute, 130F; cooling water entering jet condenser; 1510 lb/min at 70F; Temperature of mixed cooling water and condensed vapor from 4th effect: 99F; temperature of steam condensate from 4th effect: 155F; heat transfer surface, 4th effect: 200 sq. ft; barometer: normal; specific heat of all solutions are equal to the fraction of water in them. Calculate the overall heat transfer coefficient for 4th effect.