单母线分段式结线中母线分段断路器有什么作用？

把商品摆在合适的货架上。

①铅笔　②火腿肠　③肥皂　④本　⑤钢笔　⑥毛巾　⑦洗衣粉　⑧面包　⑨巧克力

生活用品：_______、_______、_______

文具：_______、_______、_______

食品：_______、_______、_______

阅读理解。

     They say there are three ways to experience the Grand Canyon; on foot, on mules (骡子) or by air. We

chose the first. Up early, my husband and I and our three children couldn't wait to get started. We decided

to walk along a lovely path named Bright Angel Trail.

     As we set out, I was shocked at how narrow the path was. And I couldn't help noticing that the other

tourists weren't like us. They had heavy backpacks, water bottles, and hats. But as usual we were dressed.

As the sun rose higher, Arizona's famous heat seemed to roast us. There was no shade and our legs were

aching. We decided to go back, with the girl on my back and the boys far behind. By the time we finally got

back, our legs were like jelly.

     The next day, after we'd had a long rest and a good breakfast, we were ready for another view of the

Canyon-by air. After our last walk, this would be the easiest thing in the world.

     We called to each other excitedly as the plane took off and circled around the Canyon. But the smiles on

our faces disappeared as the pilot tossed (翻转) the plane around, pretending he was going to hit the ground.

I shouted, "STOP, TAKE US BACK!" When we finally arrived back on land, once again our legs were like

jelly. We hardly spoke as we drove back.

     As I said, there are three ways to view the Grand Canyon. We never tried the mules, but personally I'd

suggest a fourth: buy yourself a good magazine like National Geographic. That way, you can see the Canyon,

without fear or tiredness.

1. Which of the following is true according to the second paragraph?[ ]

A. They made a careful preparation before the trip.

B. The children were more joyful than their parents.

C. Bright Angel Trail was not as lovely as they expected.

2. The underlined expression "Our legs were like jelly" probably means _____.[ ]

A. we were weak

B. we were unhappy

C. we were dissatisfied

D. we were disappointed

3. Which of the following best describes their Canyon trip by air? [ ]

A. It proved to be frightening.

B. It was more comfortable.

C. It turned out to be exciting.

D. It made each of them tired.

4. We can infer from the passage that _____.[ ]

A. experiencing the Canyon on mules would be the best way.

B. one needs to dress less when visiting the Grand Canyon.

C. the writer was not serious when she made the suggestion.

D. the whole family narrowly escaped from the air accident.

关于嗜铬细胞瘤，叙述正确的有（）

A.通常以常染色体显性方式遗传

B.常表现为持续性或阵发性高血压

C.最常见部位在肾上腺皮质

D.较多发生于右侧

E.需手术切除，肿瘤切除后即可获得痊愈

煤气使人中毒，主要是煤气中的（）。

A.CO₂

B.CO

C.CH₄

张三、张四和张五兄弟三人分别出资50万、70万、80万元购买某楼盘的三单元801房且安装数部空调，3人约定轮流居住。在张三居住期间，安装在外墙面的空调外机脱落砸伤行人。经查，负责安装空调的某公司安装空调外机的时候放置不当存在安全隐患。则下列关于本案的表述错误的是：( )

A．张氏兄弟如不能证明自己没有过错，则应对行人承担连带责任
B．仅仅由张三一人对行人承担赔偿责任
C．张氏兄弟即使能够举证是损害由于某公司安装空调不当造成的，仍不可以免责
D．行人可以要求张三一人承担责任，张三事后可以向张四、张五追偿相应的份额