true&false

13.- The entire simplex tableau of a linear program can be computed from knowledge of the associated inverse matrix (and the original model). Changes in the right of the constraints of a linear program can affect only the right side of its optimal tableau, that is, feasibility. Changes in any coefficients of the linear program other than the right side of its constraints can affect only the optimality of the solution. If a variable is nonbasic in the optimal tableau, changes in its original objective coefficient can affect only its objective equation coefficient in the optimal tableau, and nothing else. Changes in the objective coefficient of a basic variable in the optimal solution can change all the coefficients of nonbasic variables in the optimal tableau. 18.- When the primal problem is nonoptimal, the dual problem is automatically infeasible. If the primal has unbounded optimal, the dual is always infeasible 19