题干

X、Y、Z是3种短周期元素,其中X、Y位于同一族,Y、Z处于同一周期.X原子的最外层电子数是其电子层数的3倍.Z原子的核外电子数比Y原子少1.下列说法正确的是(   )

A:元素非金属性由弱到强的顺序为Z<Y<X

B:Y元素最高价氧化物对应水化物的化学式可表示为H3YO4

C:3种元素的气态氢化物中Z的气态氢化物最稳定

D:原子半径由大到小的顺序为Z<Y<X

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A

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    When it comes to generation gap (代沟), we usually think of different tastes in music, or pastimes. But now the generation gap is handwriting. After one teacher in Tennessee discovered that she had students who couldn't read what she was writing on the board, she posted it on the Internet saying that handwriting should be taught in schools.

    Others who are against it claim that handwriting has become out of time in our modern world. Typed words have become a main form of communication. Once a practical skill, handwriting is no longer used by most of Americans. It is no longer taught in schools, and some claim that the time that it would take to teach it could be put to better use, for example, by teaching the technical skills.

    But even in today's world there are still plenty of reasons to pick up a pen and write on the paper. In America, signatures (签字) by hand are still often required, for example, signing for a registered letter and buying a house. And original signatures are much more difficult to fake (伪造).

    There is also strong evidence that writing by hand is good for the mind. It makes a different part of the brain active and improves fine moving skills in young children. People are also more likely to remember what they write by hand than what they type, and the process of writing by hand has been shown to stimulate ideas. Not only those, studies have shown that kids who write by hand learn to read and spell earlier than those who don't.

    Yes, we live in a modern world, but we live in a modern world of basic and important values.