栽植期养护

如图所示为一单摆的共振曲线，根据曲线可求得此单摆摆长为       ，若该单摆的摆长变短，则此共振曲线振幅A最大值对应的横坐标f的值将      （选填“增大”、“减小”或“不变”）（取g=π²）。

要求评标时按事先公布的标准对待所有的投标人，体现了招标投标管理中的( )原则。

A．公开
B．公正
C．公平
D．诚实信用

电解原理在化学工业中有广泛应用。如图表示一个电解池，装有电解液a；X、Y是两块电极板，通过导线与直流电源相连。请回答下列问题

(1)若X、Y都是惰性电极，a是饱和NaCl溶液，实验开始时，同时在两边各滴入几滴酚酞试液，则：

①Y电极上的电极反应式为_________________。

②在X极观察到的现象是_________________。

(2)如果在铁件的表面镀铜以防止铁被腐蚀，电解液a选用CuSO₄溶液，则：

①X电极对应的金属是___________（填元素名称），其电极反应式为___________________。

②若电镀前铁、铜两片金属质量相同，电镀完成后将它们取出洗净、烘干、称量，二者质量差为5.12g，则电镀时电路中通过的电子为______mol。

③镀层破损后，镀铜铁比镀锌铁更容易被腐蚀，请简要说明原因：______________________。

阅读理解。

     Anthony Horowitz was miserable (痛苦的) as a child.He was, as he puts it, "not very bright"

and couldn't win the attention of his very wealthy parents, who preferred his "clever" older brother

.At age 8, Horowitz was sent away to an abusive (虐待的) boarding school in his native England,

even though he screamed and pleaded (恳求) with his parents year after year not to send him."The

thought was, 'It'll be good for him' ," Horowitz recalls (回忆)．

     It was not.Horowitz did badly in his studies, had few friends and was bullied (欺负) for five

years."My teachers couldn't have had a lower opinion of me," he said."I wasn't even smart enough

to rebel (反抗)．One thing I remember from the very earliest age was this desire to write.When

I was 10 years old, I remember asking my parents to get me a typewriter for my birthday because

I wanted to be a writer."

     Now, at 55, Horowitz is one of the world's most successful children's book authors.His Alex

Rider series has sold more than 5 million copies, and the eighth book featuring the young spy,

Crocodile Tears, came out this month.

     The Alex Rider books tell the adventures of 14yearold Alex Rider, an agent for the British

intelligence agency MI6.

     Horowitz said he doesn't try to write for kids; it just comes out that way."I have a feeling it's

to do with purity and simplicity.I give as little information as is necessary to describe the room,

the character in the room, and get on with the action," he said.

     That style has also made Horowitz a successful writer of television shows for adults in Britain

because, he says, writing books for kids is a lot like writing television for grownups.In both cases,

it's all about entertaining people with a good story.

     Now, Horowitz couldn't be happier with his life.He sums up his success: "…you can be anything

you want to be if you just believe in yourself.I do believe it completely."

1．The text is mainly about________.

A．Horowitz's popular book-Alex Rider

B．Horowitz's miserable childhood

C．Horowitz, a successful children's writer

D．Horowitz's special writing style

2．In his childhood, Anthony Horowitz________.

A．was more intelligent than his brother

B．was paid more attention by his parents

C．couldn't understand why he was sent to the boarding school

D．led a miserable life because of poverty

3．Which of the following is TRUE of Anthony Horowitz?

A．He was the beloved child of his family.

B．He benefited a lot from boarding school.

C．He emphasizes the plot rather than character in stories.

D．Although he is successful, he isn't very happy.

4．What advice does Horowitz have for readers?

A．Confidence is the key to success.

B．Hardship teaches valuable lessons.

C．Interest is the best teacher.

D．Diligence is the parent of success.

某船舶的宽深比为2.4稳性衡准数为1.5，按我国法定规则规定，该船的极限倾角和稳性消失角均可适当减小（）。

A.5°

B.4°

C.3°

D.2°