please solve part a

Consider the following problem.

Maximize Z c1x1 c2x2,

subject to

2x1 x2 b1

x1 x2 b2

and x10,x20. Let x3 and x4 denote the slack variables for the respective functional constraints. When c1=3,c2=2,b1=30, and b2=10, the simplex method yields the following final simplex tableau. I (a) Use graphical analysis to determine the allowable range for c1 and c2. and x10,x20. Let x3 and x4 denote the slack variables for the respective functional constraints. When c1=3,c2=2,b1=30, and b2=10, the simplex method yields the following final simplex tableau. I (a) Use graphical analysis to determine the allowable range for c1 and c2