写出一个具体的y随x的增大而减小的一次函数解析式___________

如下图所示，标有“6V、3W”字样的小灯泡与最大阻值为10Ω的滑动变阻器串联在电路中．当变阻器连入电路中的电阻为6Ω时灯正常发光．（不考虑灯泡电阻受温度影响，电源电压不变）求：

（1）灯泡电阻、电源电压；

（2）灯泡正常发光1min，变阻器产生的热量．

当城市用配备GPS的出租车获取城市实时路况时，其所获取数据存在的主要质量问题是（）

A.位置精度，因为GPS定位不准确

B.完整性，因为出租车反应的路况并不全面

C.属性精度，因为无法获取每辆出租车的属性

D.时间精度，因为时间记录存在误差

简述同质结构的群体可能达到最高工作效率的条件？

小敏同学在练习连接电流表的实验中，连好电路闭合开关试触时，发现电流表指针偏转到如图所示的位置，于是立即断开开关．产生这种现象的原因是： _________ ，为了能够继续实验，应该 _________ ．

阅读理解。

     The first day of school our professor introduced himself and challenged us to get to know someone

we didn't know. I stood up to look around when a gentle hand touched my shoulder. I turned around

to find a wrinkled, little old lady beaming up at me with a smile that lit up her entire being.

     She said, "Hi, girl! My name is Rose. I'm 87 years old. Can I give you a hug?"

     I laughed and enthusiastically(热情地)responded, "Of course you may!" and she gave me a giant

squeeze.

     "Why are you in college at such a young, innocent age?" I asked. She jokingly replied, "I'm here

to meet a rich husband, get married, have a couple of children, and then retire and travel!"

"     No seriously," I said. I was curious what may have motivated her to be taking on this challenge

at her age.

     "I always dreamed of having a college education and now I'm getting one!" she told me.

     Over the course of the year, Rose became a campus icon and she easily made friends wherever

she went. She loved to dress up and she reveled in the attention bestowed upon her from the other

students. She was living it up.

     At the end of the semester we invited Rose to speak at our football banquet. I'll never forget what

she taught us.

     "We do not stop playing because we are old; we grow old because we stop playing. There are

only two secrets to staying young, being happy, and achieving success. You have to laugh and find

humor every day. You've got to have a dream. When you lose your dreams, you die!" she said.

     "There is a huge difference between growing older and growing up. If you are nineteen years old

and lie in bed for one full year and don't do one productive thing, you will turn 20 years old. If I am

87 years old, and stay in bed for a year, and never do anything, I will turn 88. Anybody can grow

older. But every minute counts for young men," she added.

     "The idea is to grow up by always finding the opportunity in change.Have no regrets. The elderly

usually don't have regrets for what we did, but rather for things we did not do.The only people who

fear death are those with regrets."

      She concluded her speech by courageously singing The Song of Rose.She challenged each of us

to study the lyrics(歌词)and live them out in our daily lives.

     At the year's end, Rose finished the college degree she had begun all those years ago.One week

after graduation Rose died peacefully in her sleep.

1．Rose made herself known to the author in a________ manner.

A．serious  

B．cold

C．humorous  

D．crazy

2．From the information provided in the passage, we know ________.

A．Rose finished the college degree within a year

B．Rose did realize her dream of meeting a rich husband and getting married through college education

C．Rose enjoyed her campus life very much

D．Rose grew so old that she stopped playing

3．Rose delivered the speech________.

A．at the graduation

B．which she prepared carefully

C．ended with The Song of Rose

D．to challenge all the other speakers

4．According to her speech, ________.

A．even you have a dream, you won't succeed

B．all people don't grow up while growing older

C．Rose usually regretted having done something

D．a nineyearold is as old as an 87yearold if he doesn't do anything