单级单吸泵的叶轮上开有()以平衡轴向力。
参考答案:平衡孔
After the robbery, the jewelry shop fixed an alarm system ______ further losses. [ ]
A. for
B. from
C. against
D. toward
下列哪项体征不是Horner征()
A.眼裂
B.瞳孔
C.面部出汗增加
D.眼球内陷
E.用力睁眼时,眼裂两侧等大