A wet solid is to be dried in a tray dryer under steady-state conditions from a free moisture content of X ₁ = 0.40 kg H ₂ O/kg dry solid to X ₂ = 0.02 kg H ₂ O/kg dry solid. The dry solid weight is 99.8 kg dry solid and the top surface area for drying is 4.645m ² . Calculate the time for drying using a straight line through the origin for drying rate in the falling-rate period.