Consider the following statements:
1. A linear programming problem with three variables and two constants can be solved by graphical method
2. For solutions of a linear programming problem with mixed constraints, Big – M method can be employed
3. In the solution process of a linear programming problem using Big – M – method, when an artificial variable leaves the basis, the column of the artificial variable can be removed from all subsequent tables
Which of these statements are correct?
(a) 1,2 and 3 (b) 1 and 2
(c) 1 and 3 (d) 2 and 3