气管插管的保留时间不宜超过（）。 A.12h B.24h C.36h D.48h E

某基坑深7m，0～30m为粉细砂，地下水位为4．0m，现拟采用井点法进行基坑降水，井深20m，渗流计算的类型为（）。

A.潜水非完整井

B.潜水完整井

C.承压水非完整井

D.承压水完整井

该病人的治疗不恰当的是

A．休息

B．理疗

C．抗生素

D．不要挤压

E．及早切开引流

If you ________ at school, you _______ a college student now.

A．had studied hard; would have been

B．should have studied hard; should have been

C．had studied hard; would be

D．would study hard; must have been

前磨牙支托的宽度为（ ）。

A．其颊舌径1/2

B．其颊舌径1/3

C．其颊舌径1/4

D．其近远中径的1/5

E．其近远中径的1/6

测定含Cr和Mn的钢样中的Cr和Mn含量时，钢样溶解后Cr和Mn以（）和（）形式存在。

A.

B.

C.

D.