In network simplex method, which formulation is used to find the entering variable xj, and what is the criteria? (b) (4 pts) Ha point is feasible to an integer programming (IP) problem with...

In network simplex method, which formulation is used to find the entering variable xj, and what is the criteria?
(b) (4 pts) Ha point is feasible to an integer programming (IP) problem with maximization objective, does its corresponding objective value provide a lower bound or upper bound for this IP problem?
(c) (4 pts) In the branch-and-bound algorithm, if the LP relaxation has a solution xi = 2, x2 = 3.6, x3 = 1, which one we should choose to branch? How can we branch to get two subproblems?




Problems must be complete by hand.