13. Consider the LP Maximize z = ex subject to (A, I)X =

b, X ;;:::: 0 Define Xn as the current basic vector with B as its associated basis and eB as its vector of objective coefficients. Show that if eB is replaced with the new coefficients DB, the values of Zj - Cj for the basic vector XB will remain equal to zero. What is the significance of this result?

L In Example 7.2-1, summarize the data of iteration 1 in the tableau format of Section 3.3.