Exercise 4 6y₁ + 3y2 + Y3 +Y4: Consider the following Linear Programming problem: max -Y1 + 2y2 +Y4 ≤ 2 -Y1 - Y2 + Y3 + 2y4 ≤ 3 Yi ≥ 0 1. find its dual problem; 2. find the extreme points of the feasible set of the dual problem; 3. find the optimal solutions of both problems.