Here is the initial Big-M non-tableau for a Maximization LP

z	x1	x2	x3	s1	s2	e3	a3	RHS
1	-10	-8	-4	0	0	0	1000	0
0	12	0	1	1	0	0	0	120
0	2	1	3	0	1	0	0	90
0	25	17	20	0	0	-1	1	24

and here is the optimal tableau corresponding to BV = { s1 , e3 , x2 }

z	x1	x2	x3	s1	s2	e3	a3	RHS
1	6	0	20	0	8	0	1000	720
0	12	0	1	1	0	0	0	120
0	9	0	31	0	17	1	-1	1506
0	2	1	3	0	1	0	0	90

In each question, write the value of a vector in horizonal format, separating entries with comma's and NO SPACES. Also do not include brackets or parentheses

1. What is the value of c~x1

2. What is the reduced cost for x3

3. What would be the new value of c~x1if c1 is changed to 18 Note, we keep BV the same

4. What would be the new value of c~x3 if c3 is changed to 18 Note, we keep BV the same

5. Which tableau (part 3 or part 4) will still be an optimal tableau?