Q$-5.$ Use the branch and bound algorithm to determine the solution to the following integer programming problem $($complete the tree below$).$

Solutions for all possible branches are given in the table on page $8.$

$($Mark on the table LP# you used$)$

Min. $Z=51+42$

$s.t.31+22=>5$

$21-32=>7$

$..............(2)$

$x1,x2=>>0$ and Integer