$]12,000[x_1$

The optimal solution is: $x_1=,x_2=x_3=x_4=$

The best objective function value is: $$

$5.$

Max $30000x_1+22000x_2+24000x_3+8000x_4$

$S.T.800x_1+400x_2+500x_3+100x_{4}15,000$

$x_1,10$

$x_2,10$

$x_3,10$

$x_{4}10$

$x_1+x_2,6$

$800x_1,-500x_3-100x_{4}0$

$x_1,x_2,x_3,x_{4}0$

The optimal solution is:

$x_1=x_2=x_3=x_4=$

The best objective function value is: $$