用于定性的参数是
A．色谱峰高或峰面积B．死时间C．色谱峰保留时间D．色谱峰宽E．色谱基线
参考答案：C
Ebstein畸形的典型表现（）|二尖瓣狭窄合并关闭不全的典型表现是（）
A.左房大、左室小、主动脉结小
B.左房大、左室大、主动脉结小
C.右房大、左室大、主动脉结小
D.右房大、右室大、主动脉结小
E.右房大、右室小、主动脉结小
It is said that the gravity on Mars is only about __________ of the gravity on earth．
A．three-eighths
B．third-eighth
C．three-eighth
D．third-eighths
