Find the minimum and maximum of the function z=5x-4y subject to y>=2, y<=7, 5x-3y>=-6, 5x+y<=42. What are the corner points of the feasible set?
a) Minimum is (-4,2), maximum is (6,7)
b) Minimum is (0,2), maximum is (8,7)
c) Minimum is (0,2), maximum is (7,7)
d) Minimum is (2,2), maximum is (8,7)