The experimental average diffusion coefficient of moisture in a given apple piece is 7.6x10-40 m/s. Large slabs of apple, 30 mm thick, are dried from both sides by air having a humidity and temperature such that the equilibrium moisture content in the apple is X*= 0.05 kg H30/ kg dry apple. Assuming no shrinkage during drying and direction of diffusion is perpendicular to slab and only diffusion of moisture controls the drying process. a. (7 %) Calculate the time needed to dry the given apple slab from a total average moisture content of X, ;=0.30 kg H-0/ kg dry apple to X.=0.10 kg H-0/ kg dry apple. b. (7 %) Justify your answer in part a using Heissler chart to calculate the time needed for drying. Assume average concentration with negligible surface resistance. c. (11 %) You would like to dry mustard seeds from initial moisture content of 45% to the critical moisture content of 10% where equilibrium moisture content is 5% using a conveyor dryer. The drying air enters and flows countercurrent to the solids at a flow rate of 3850 kg dry air/h at 120C with a humidity of 0.055 kg/kg dry air. The conveyor belt is 1 m wide and is loaded with 200 kg feed/h. The belt moves with a velocity of 20 m/h. If the length of the conveyor (dryer) is 15 meters, calculate the required mass transfer coefficient, k,M(kg dry air/m.h) in order to perform the desired drying process. Assume adiabatic drying occurring only from top