紧急电动运行开关本身或通过另一个符合电气安全装置规定的电气开关应使轿厢上行超速保护装

The death list in a school bus accident that happened on Wednesday morning in the northwest province of Gansu has risen to 20 following the death of one child later Wednesday.

It’s known that the accident happened around 9:40 a.m. in Yulinzi town of Zhengning county, according to a report from the police. The report said five people including four children and their bus driver died just at the moment that the accident happened. While 15 others, their teacher included, were sure to be dead by the afternoon.

It’s reported that another 44 children were injured in the accident and have been sent to hospital. Twelve of the injured are in badly hurt. The truck which caused the accident was carrying coal. Another reason for the accident was the bus itself. The police has blamed(谴责）overloading for the accident, saying that the bus -- a van with nine seats -- was carrying 64 people.

小题1:Where did the accident happen on a Wednesday morning?

A．In Yushu,Gansu

B．In Yulinzi county,Gansu

C．In Zhengning,Gansu

D．In Zhengning town,Gansu小题2:How many more people did the bus carry than it could be carried in?

A．9

B．15

C．64

D．55小题3:What does the underlined word“ovrerloading” mean ?

A．loading on the Internet

B．carrying much more than usual

C．carrying coals

D．carrying people

关于专用X线机的叙述，不正确的是（）

A.胃肠专用机多配用增强电视系统

B.乳腺机的千伏调节范围一般20～40kV

C.床边专用机也采用逆变式高压发生器

D.C形臂、导管床用于心血管专用机

E.牙科机即口腔全景摄影机

经营利润的变动对销售变动反映程度的衡量指标是（）

A、财务杠杆系数

B、流动比率

C、速动比率

D、经营杠杆系数

球团矿的强度指标主要是（），一般规定≥5mm的≥84%。