单项选择题
A.确定离基变量B.确定进基变量C.进行换基运算D.确定最优基
A.B.C.D.
A.(1,1,-2,0,0)B.(0,0,1,4,0)C.(0.4,1,0,0,0)D.(0,0,0,0.3,2)