当电力系统出现（）时，将出现零序电流。A、不对称运行B、三相故障C、相间故障D、接地

The nurse preparing to give a child an intramuscular injection chooses to give the injection into the gluteal muscle. The site is acceptable because which of the following reasons

A. The child has been walking for 1 year.
B. The child has small deltoid muscles.
C. The child is older than 2 years.
D. The child weighs more than 25 pounds.

下列词语中，没有错别字的一组是

A．熨帖过度期一筹莫展失之毫厘，差之千里

B．恪守颤悠悠方兴未艾有则改之，无则加免

C．湎怀露马脚提纲挈领一言既出，驷马难追

D．商榷里程碑严惩不贷一叶障目，不见泰山

[计算题]某泵30min内输送石油13m³，求体积流量和重量流量（ρ₂₀=830kg/m³）？

下列哪项属于内部招聘的特点是（）。

A.可信度高

B.激励性不强

C.费用高

D.有利于招到优秀人才

旅店的服务员，进行一次健康体检的时间间隔是（）

A.3个月

B.6个月

C.12个月

D.18个月

E.24个月