The change of free moisture content $($X$)$ and time $($t$)$ of a food item is given below. The amount of dry solid is $15$ kg and this material is dried in a $2$ m$^2$ dryer.a$)$ Draw a graph of drying rate $($R$)$ versus free moisture content $($X$)$ for this food item. Determine the critical free moisture content $($Xc$)$ and the constant drying rate $($Rc$).($Note: Show at least two calculations of R and X$)$b$)$ Determine the required drying time from X $0\mathrm{.}1$ to X$-0\mathrm{.}05.$ Assume that R is a linear function of X in this period. The change of free moisture content $($X$)$ and time $($t$)$ of a food item is given below. The amount of dry solid is $15$ kg and this material is dried in a $2$ m$^2$ dryer.