站坪设在曲线上的缺点是什么？

ALB
B. AMG
C. 免疫球蛋白
D. TRP
E. AFP

A. 头皮电极
B. 皮下电极
C. 夹式电极
D. 鼻咽电极
E. 蝶骨电极

A. either all the way open or all the way closed
B. normally open
C. throttled depending on load
D. controlled by suction pressure