It is desired to dry a certain type of fiberboard in sheets 0.131 m x 0.162 m x 0.071 m from 59% to 4% moisture (Wet basis) content. The rate of drying at constant rate period was found to be 8.0 kg/m h. The critical moisture content was 24.8% and the equilibrium moisture content was 1.0%. The fiberboard is to be dried from one side only and a bone dry density of 299 kg/m. Determine the time required for drying. Assume the falling rate is linear. (12) (April '99).