1 2 2 3 4 () A．5 B．7 C．8 D．9

有人设计出利用CH₄和O₂的反应，用铂电极在KOH溶液中构成原电池。电池的总反应类似于CH₄在O₂中燃烧，则下列说法正确的是 [ ]

①在标准状况下，每消耗5.6L CH₄可以向外电路提供2mole^－ ②通过甲烷电极的电极反应式为：CH₄+10OH^－－8e^－=CO₃^2－+7H₂O ③通过甲烷的电极为电池的正极，通过氧气的电极为负极 ④电池放电后，溶液pH不断升高

A．①②              

B．①③              

C．①④          

D．③④

Jim often goes to movies _____ his friends.[ ]

A. and

B. to

C. with

根据句意及首字母或汉语提示完成单词（每小题1分，满分10分）

小题1:Daniel is clever, but he never shows off. He is m     .

小题2:A f      teacher   should  treat each student equally.

小题3:Don’t p______   her anything if you don’t want to get into trouble.

小题4:It’s difficult to make a ______（决定）to give up smoking.

小题5:You will have less d_______ learning English with your teacher’s help.

小题6:Tom didn’t go to bed until midnight yesterday. He feels very______(sleep)at the moment.

小题7:The boy is very lazy and his parents feel very______(worry)about him.

小题8:Mary _____(prefer)milk to coffee when she was young.

小题9:After taking the driving test, the man feels_________(relax).

小题10:The Chinese people have lots of______(wise)and create many wonders.

数据访问页有两种视图方式，分别为______和______。

已知向量a=（cosα，sinα），b=（cosβ，sinβ），c=（-1，0）。

（1）求向量b+c的长度的最大值；

（2）设，且α⊥（b+c），求cosβ的值。