Five thousand lb/h of wet isophthalic acid crystals with 30 wt% moisture (wet basis) at 30°C and 1 atm enter an indirect-heat steamtube rotary dryer, where they are dried to a moisture content of 2 wt% (wet basis) by 25 psig steam (14 psia barometer) condensing inside the tubes. Evaporation takes place at 100°C, which is also the exit temperature of the crystals. The specific heat of isophthalic acid is 0.2 cal/g-°C. Determine: 

(a) Rate of evaporation of moisture; 

(b) Rate of heat transfer; 

(c) Quantity of steam required in lb/h.