Q$4/$ An absorption refrigeration system using an $NH3-H2O$ system is shown in Figure $1.$ The purpose of the cycle is to absorb $8106Bt\frac{u}{h}r$ of energy as heat into the refrigerator at a temperature of about $0C.$ For the conditions shown, calculate

a$)$ The amount of $97\mathrm{.}5wt\%NH3$ going to the refrigerator.

b$)$ The concentration and quantity of strong liquor fed to the column.

c$)$ The minimum reflux ratio. Assume that the strong liquor enters the column as saturated liquid.

d$)$ The number of theoretical stages in the column and the number of such stages below the feed point if the reflux ratio is $1\mathrm{.}5$ times the minimum.