It's a Mass transfer 2 numerical problem . Please solve it

2. A batch of wet solid is to be dried from a free moisture content of 0.38kg water/kg dry solid to a final moisture content 0.04kg water /kg dry solid, area =18.6m2 of top drying surface, critical moisture content is 0.195kg water/kg dry solid. Calculate the time of drying. Weight of dry solid is 399kg. Data for falling rate period is given below. 6