集合A=d，b，c上的二元关系R为：R=＜a，a＞，＜c，c＞，＜a，b＞，则二元关

能源技术的创新不断地推动人类社会的进步，但能源危急、环境污染和生态破坏又反过来制约人类社会的发展，作为一名现代社会的中学生，你会发现周围很多能量白白浪费了，利用学过的物理知识，将一些能量转化为电能：

（1）请你为自己的家庭设计两个不需要消耗燃料的发电方式：　 　、　 　

（2）大海海面波浪起伏，你想过将波浪所具有的机械能转化为电能给灯塔供电吗（提示：地磁场磁性太弱）？请回答下列问题：

A．这一设想依据的原理是：　 　

B．需要的器材：除导线、开关外，还需要两个关键器材：　 　、　 　

C．怎么实现你的设计？

计算机网络的安全是指

A．网络中设备设置环境的安全

B．网络使用者的安全

C．网络可共享资源的安全

D．网络的财产安全

阅读理解。

     The latest research suggests that the key factor separating geniuses from the merely

accomplished is not IQ, a generally bad predictor of success. Instead, it's purposeful

practice. Top performers spend more hours practising their craft. If you wanted to

picture how a typical genius might develop, you'd take a girl who possessed a slightly

above average language ability. It wouldn't have to be a big talent, just enough so that

she might gain some sense of distinction. Then you would want her to meet, say, a

novelist, who coincidentally shared some similar qualities. Maybe the writer was from

the same town, had the same family background, or shared the same birthday.

     This contact would give the girl a vision of her future self. It would give her some

idea of a fascinating circle she might someday join. It would also help if one of her parents

died when she was 12, giving her a strong sense of insecurity and fuelling a desperate need

for success. Armed with this ambition, she would read novels and life stories of writers

without end. This would give her a primary knowledge of her field. She'd be able to see

new writing in deeper ways and quickly understand its inner workings.

     Then she would practise writing. Her practice would be slow, painstaking and errorfocused.

By practising in this way, she delays the automatizing process. Her mind wants to turn conscious,

newly learned skills into unconscious, automatically performed skills. By practising slowly, by

breaking skills down into tiny parts and repeating, she forces the brain to internalize a better

pattern of performance. Then she would find an adviser who would provide a constant stream

of feedback, viewing her performance from the outside, correcting the smallest errors, pushing

her to take on tougher challenges. By now she is redoing problems-how do I get characters into

a room-dozens and dozens of times. She is establishing habits of thought she can call upon in order

to understand or solve future problems.

     The primary quality our young writer possesses is not some mysterious genius. It's the ability to

develop a purposeful, laborious and boring practice routine. The latest research takes some of the

magic out of great achievement. But it underlines a fact that is often neglected. Public discussion is

affected by genetics and what we're "hardwired" to do. And it's true that genes play a role in our

capabilities. But the brain is also very plastic. We construct ourselves through behaviour.

1．The passage mainly deals with ________.

A．the function of IQ in cultivating a writer

B．the relationship between genius and success

C．the decisive factor in making a genius

D．the way of gaining some sense of distinction

2．By reading novels and writers' stories, the girl could________.

A．come to understand the inner structure of writing

B．join a fascinating circle of writers someday

C．share with a novelist her likes and dislikes

D．learn from the living examples to establish a sense of security

3．In the girl's long painstaking training process, ________.

A．her adviser forms a primary challenging force to her success

B．her writing turns into an automatic pattern of performance

C．she acquires the magic of some great achievement

D．she comes to realize she is "hardwired" to write

4．What can be concluded from the passage?

A．A fuelling ambition plays a leading role in one's success.

B．A responsible adviser is more important than the knowledge of writing.

C．As to the growth of a genius, IQ doesn't matter, but just his/her effort.

D．What really matters is what you do rather than who you are.

副团级大队及其相当的建制单位，执行（）单位奖励权限。

A.团级

B.副团级

C.营级

D.副营级

产前检查覆盖率是反映下列哪项内容的指标

A．疾病严重程度

B．卫生服务需要量

C．卫生服务利用

D．卫生资源

E．疾病频度