minimize subject to x1 + 3x2 - Ax3 — 5x4 − - x1 + x2 x3 + 4x4 = -1 2x1 - X2 - - 3x3 - x4 В x1, x2, x3, x4 ≥ 0 (a) Find all values of ẞ for which the LPP has a BFS x* whose basic variables are x3 and x4. Express x* is terms of ẞ: x* = - (b) For the x* you found in (a), find the reduced cost č; = c; — c—B˜¹A; for the basic direction j = 1.