Use Dual Simplex Method to solve the following problem:
$\begin{array} \text{Maximize} & z=-2x_1-3x_2 \\ \text{subject to:} & \\ & x_1+x_2 \geq 2 \\ & 2x_1 +x_2 \leq10 \\ & x_2 +x_2 \leq 8 \\ & x_1,x_2 \geq 0 \end{array}$
- $x_1=2, x_2=0, \text{ and } z=-4$
- $x_1=2, x_2=6, \text{ and } z=-22$
- $x_1=0, x_2=2, \text{ and } z=-6$
- $x_1=6, x_2=2, \text{ and } z=-18$