Consider the knapsack problem given below.

Max $Z=x_1+4x_2+2x_3+6x_4$

$S.t.3x_1+8x_2+3x_3+6x_{4}13$

$x_1,x_2,x_3,x_4=0or1.$

Use branch and bound method to solve the problem as described in part a and $b$ below.

a$.$ State your Subproblem $1$ and find its solution. $(10$ P$)$

b$.$ State your Subproblem $2$ and Subproblem $3($do not solve Subproblem $2$ and Subproblem $3!).$

$(4$ P$)$