max z $=40$x$1+50$x$2$

s$.$t$.$ x$1+2$x$2<=40$ hr$.$ of labor

$4$x$1+3$x$2<=120$ lb$.$ of clay

x$1,$ x$2>=0($x$1$: number of bowls, x$2$: number of mugs$)$

This is a standard linear programming model; as such, it has a single objective function for profit. However, let us suppose that instead of having one objective, the pottery company has several objectives, listed here in order of importance: $1.$ To avoid layoffs, the company does not want to use fewer than $40$ hours of labor per day. $2.$ The company would like to achieve a satisfactory profit level of $$1,600$ per day. $3.$ Because the clay must be stored in a special place so that it does not dry out, the company prefers not to keep more than $120$ pounds on hand each day. $4.$ Because high overhead costs result when the plant is kept open past normal hours, the company would like to minimize the amount of overtime. Solve the problem as a GP$.$