旅行社组织旅游活动不得有哪些行为？

为了研究物质之间反应的质量关系，小李同学作了如下实验：将6g镁分别在不同质量的氧气中充分燃烧，请将生成氧化镁的质量填入下表：

序号	氧气（g）	生成的氧化镁（g）
1	2
2	4
3	8
4	10

根据以上数据，回答：

（1）上述4次实验中，第______次氧气过量；第______次镁过量．

（2）解释为什么后面几次实验中，虽然氧气的量不断增加，但是生成的氧化镁的质量却不再增加？

WHAT happens to a teenage kid when the world he thought he knew suddenly changes? Find out in Little Brother by American author Cory Doctorow． It is a fascinating book for a new generation of sci-fi readers．

Marcus Yallow, 17, from San Francisco is much more comfortable in front of a computer than obeying the rules of society． Smart, fast and wise to the ways of the networked world, he has no trouble outwitting （骗过） his high school's monitoring system． This way he and his friends get to head off to play a popular online game in real life．

While they are playing, a bomb explodes on the Bay Bridge． Marcus stops a military vehicle to get help for his injured friend, but this simple act throws him into a Department of Homeland Security （DHS） secret prison． There he is treated as a possible terrorist． He is eventually let go after four days, but his injured friend disappears．

When he returns, Marcus discovers that there are many "security measures" in place and that now all citizens are treated like potential terrorists． While some consider this government action necessary for public safety, Marcus sees this as a complete destruction of the rights he is supposed to have as a citizen．

He knows that no one will believe his story, which leaves him with only one thing to do: to take down the DHS himself． He helps organize a large network called Xnet to spread the truth, anonymously （匿名地）．

The book presents a young man who is irresponsible, but learns about himself, and grows, in the course of the story． As part of this learning and growing he becomes aware of very serious issues about his society．

小题1: What kind of article does this passage belong to?     

A．A fascinating story．

B．A book review．

C．News report

D．A TV programme小题2: The underlined word destruction in the passage means         ．     

A．damage

B．reward

C．ruin

D．protection小题3: Marcus Yallow was sent to prison because         ．        

A．he killed his friend

B．he bombed a military vehicle

C．he did something that a possible terrorist could do

D．his injured friend disappeared小题4: From the second paragraph we can infer that         ．     

A．Marcus Yallow is much more comfortable obeying the rules of society

B．Marcus Yallow is smart, fast and wise in real life

C．Marcus Yallow always plays online games in real life

D．Marcus Yallow is expert at the network world小题5: In the end of the book, Marcus Yallow         ．      

A．is supposed to be more irresponsible

B．becomes aware of very serious issues about his society

C．presents a young man who is irresponsible

D．plays a popular online game in real life

质量为1.5Kg的物体在水平拉力F的作用下，从水平面上A点由静止开始运动，滑行t=2.0s到B点，已知AB两点的距离L=2.0m，物体与水平面间的动摩擦因数为0.20，求水平拉力F的大小？

男性，55岁，间断、全程、无痛性肉眼血尿半年多，无其他症状。查体：双侧肾区未及肿物，无叩击痛，耻骨上区未及肿物，无压痛，左侧阴囊可触及蚯蚓状团块，平卧后不消失。下列哪项检查最合适（）

A.阴囊多普勒超声

B.膀胱镜

C.B超

D.静脉肾盂造影

E.腹部X平片

主要体现为气与血关系的是()
主要表现在血液方面关系的是()

A.心与肺

B.心与脾

C.心与肝

D.心与肾

E.肝与肾