Describe how a two-phase improving search of a model with original variables y1, y2, and y3 would proceed if Phase I search terminated as follows:

(a) Global optimum y = 140, 7, 0, 9, 02

(b) Global optimum y = 16, 3, 1, 0, 02

(c) Local optimum y = 11, 3, 1, 0, 02

(d) Local optimum y = 10, 5, 1, 2, 02, which may not be a global optimum