Consider the following statements regarding the characteristic of the standard form of a linear programming problem:
1. All the constraints are expressed in the form of equations.
2. The right – hand side of each constraint equation is non – negative.
3. All the decision variables are non – negative.
Which of these statements are correct?
(a) 1,2 and 3 (b) 1 and 2
(c) 2 and 3 (d) 1 and 3