A.介于-∞到+∞ B.介于0到+∞ C.介于-∞到0
A.甲=14,乙=18.32,丙=0.472 B.甲=14,乙=13.5,丙=0.472 C.甲=14,乙=18.32,丙=0.169 D.甲=13,乙=18.32,丙=0.472