六碳糖中，（）和（）最易发生非酶褐变。

下面左图为“某城市及其周围地区某日14：00等温线分布示意图”，读图完成1~2题。

1、左图中气温最高的是[ ]

A、甲　　　

B、乙　　　

C、丙　　　

D、丁

2、右图中反映城郊间热力环流的是 [ ]

A、①　　　

B、②　　　

C、③　　　

D、④

一老年患者习惯性便秘，大便3日一次，干结如羊粪状，伴口干咽燥，皮毛干枯，舌红少津，脉细。

需注意避免应用的药物是（）

A.火麻仁

B.桃仁

C.何首乌

D.当归

E.雄黄

某同学为了观察一个塑料小球下落的运动情况，他将小球上端连接一纸带，纸带穿过打点计时器(如图甲所示)，让小球自由下落，打出的纸带由A到E，如图乙所示，关于小球运动状态和受力情况，下列说法正确的是

A．AE段小球是匀速运动，球和纸带的重力等于向上的阻力

B．AC段小球是减速运动，球和纸带的重力小于向上的阻力

C．CE段小球是匀速运动，球和纸带的重力等于向上的阻力

D．CE段小球是匀速运动，球和纸带的重力小于向上的阻力

简述电子商务产品的发展趋势。

阅读理解。

    Mobile phones have become a problem for middle schools. Some middle schools in Australia have prevented

students from carrying mobile phone during school hours.

    Mobile phone use among children has become a problem for the school this year. Several children have got

mobile phones as Christmas gifts, and more students will want them.

    Mary Bluett, an official, said mobile phone use is a distraction (伤心的事) to students during school hours

and it also gives teachers so much trouble in their classrooms. Teachers were also saying that sometimes

students might use phone messages to cheat during exams.

    She said some schools had tried not to let students use mobile phones at school. Some parents felt unhappy

because they couldn't get in touch with their children.

     Many teachers said students should not have mobile phones at school, but if there was a good reason, they

could leave their phones at school offices. They also said there were many reasons why the students should

not have mobile phones at school. They were easy to lose and were a distraction from studies.

     Many people say that they understood why parents would want their children to have mobile phones, but

they think schools should let the students know when they can use their mobile phones.

1. Middle schools are prevented from carrying mobile phones _____. [ ]

A. because they often talk with their friends

B. when they are free from homework

C. when they are at school

D. because they cheat in exams

2. Some children get mobile phones _____. [ ]

A. by telling lies to their parents

B. by making trouble in class

C. from their parents and friends

D. from some mobile phone users

3. Which of the following statements is true? [ ]

A. No school in Australia has done anything about the mobile phone use among students.

B. Teachers don't allow the students to leave their mobile phones at school offices.

C. Some students had their mobile phones stolen at school.

D. Parents give their children mobile phones for no good reason.

4. It is implied (暗含) in the passage that _____. [ ]

A. students shouldn't have mobile phones at school except for some special reasons

B. it is impossible to stop students from using mobile phone at school

C. some parents felt unhappy because they couldn't use their phones at school

D. parents should teach their children how to use mobile phones during school hours