比重不同的矿石，其磨矿浓度相同。

When visiting Beijing, the Palace Museum is a must-see for many people.

Last year, the museum received 14.2 million visitors, which is twice the number of visitors in 2002. This year it is expected to increase by 10 percent. Compared with other popular museums around the world, the number of visitors at the Palace Museum is very high. Last year the Louvre(罗浮宫) in Paris welcomed 8.8 million visitors and the British Museum in London received 5.8 million.

A large number of visitors can bring a lot of money from ticket sales. But there are also worries that people will do demage(破坏) to relics(文物) and old buildings.

To solve the problem, some people suggested taking cultural objects out of the Palace Museum. In this way, visitors coming for ancient buildings and cultural objects will go to different places. “It is a sign of progress. Letting more people see these treasures is more important than keeping them in their original(原始的) place,” said Song Xiangguang, a professor at Peking University.

However, Shan Jixiang, director of the Palace Museum, doesn’t agree on this idea. He thinks that the most important thing in protecting the Palace Museum is to keep it complete. “The 1.8 million cultural relics and the historical buildings are two key parts of the museum. They can’t be separated.” he said.

Shan said that they are planning to increase the space that is open to the public. This will not only feed visitors’ curiosity(好奇), but also spread them out so they are not putting too much pressure on one area.

Shan also wanted to set up an appointment system. “ If visitors make an appointment before they come, we can make better and different visiting routes(路线) for them.” Shan said.

小题1:How many visitors did the Palace Museum welcome in 2002?

A．14.2 million

B．8.8 million

C．5.8 million

D．7.1 million小题2:Why did some people suggest taking cultural objects out of the Palace Museum?

A．To let more people see the relics.

B．To bring less damage to the relics.

C．To make more money from ticket sales.

D．To keep the Palace Museum original.小题3:The underlined word “separated” means ______ in Chinese.

A．分离

B．破坏

C．偷窃

D．压迫小题4:By reading the article, we can know that______________.

A．the Palace Museum has an appointment system now.

B．relics are the only important part of the Palace Museum.

C．the Louvre welcomed the most visitors in the world last year.

D．Shan thought that more areas of the palace should be open to public.

等腰三角形的底和腰是方程x²-7x+10=0的两根，则这个三角形的周长是______．

甲公司向乙银行贷款100万元，丙公司、丁公司为保证人。根据保证人与乙银行的约定，丙公司的保证责任为80万元，丁公司的保证责任为20万元。如果甲公司到期不能清偿债务，下列各项中，表述正确的有（）。

A.乙银行只能要求丙公司承担80万元的保证责任

B.乙银行只能要求丁公司承担20万元的保证责任

C.丙公司承担了80万元的保证责任后，可以要求丁公司承担按份责任

D.丙公司承担了80万元的保证责任后，只能向甲公司追偿，不能找丁公司

女，26岁，G₀P₀，B超检查发现子宫后壁峡部一约7cm大小的肌核突起，无任何不适，下列哪项处理最为恰当（）。

A.药物治疗

B.全子宫切除术

C.肌瘤切除术

D.暂观察，待生育后再手术

E.子宫次全切除术

气动执行机构主要由膜盖、膜片、（）和阀杆组成。

A.弹簧

B.阀座

C.阀芯

D.阀盖