已知二次函数y=x2+bx+c中，函数y与自变量x的部分对应值如下表：x…-10

小麦、水稻、玉米等粮食作物的共同特点是（　　）

①直根系 ②须根系  ③网状脉   ④平行脉  ⑤花基数是3  ⑥花基数是6  ⑦胚有1片子叶  ⑧胚有2片子叶．

A．②④⑤⑦

B．①②③④

C．②④⑥⑧

D．①③⑤⑦

Linda Evans was my best friend –like the sister I never had ,We did everything together: piano lessons ,movies, swimming , horseback riding.

When I was 13, my family moved away . Linda and I kept in touch through letters ,and we saw each other on special times — like my wedding and Linda’s. Soon we were busy with children and moving to new homes, and we wrote less often .One day a card that I sent came back , stamped “Address Unknown”. I had no idea about how to find Linda.

Over the years, I missed Linda very much. I wanted to share happiness of my children and then grandchildren . And I needed to share my sadness when my brother and then mother died, There was an empty place in my heart that only a friend like Linda could fill.

One day, I was reading a newspaper when I noticed a photo of a young woman who looked very much like Linda and whose last name was Wagman —Linda’s married name.“There must be thousands of Wagmans.”I thought, but I still wrote to her.

She called as soon as she got my letter, “Mrs , Tobin!”she said excitedly, “Linda Ev-ans Wagman is my mother.”

Minutes later I heard a voice that I recognized at once, even after 40 years . We laughed and cried and caught up on each other’s lives. Now the empty place in my heart is filled. And there’s one thing that Linda and I know for sure; We won’t lose each other again!

小题1:The writer went to piano lessons with Linda Evans       .

A．at the age of 13

B．before she got married

C．before the writer’s family moved away

D．after they moved to new homes小题2:They didn’t often write to each other because they       .

A．got married

B．had little time to do so

C．didn’t like writing letters

D．could see each other on special times小题3:There was an empty place in the writer’s heart because she       .

A．was in trouble

B．didn’t know Linda’s address

C．received the card that she sent

D．didn’t have a friend like Linda小题4:The writer was happy when she       .

A．read the newspaper

B．heard Linda’s voice on the phone

C．met a young woman who looked a lot like Linda

D．wrote to the woman whose last name was Wangman小题5:They haven’t kept in touch       .

A．for about 40 years

B．for about 27 years

C．since they got married

D．since the writer’s family moved away

分压电阻（）在电路中。

A、并联

B、串联

C、联结

D、以上均可

公地悲剧，也称公共地悲剧，指享用者都从自己私利出发，争取从中获取更多收益，而付出的代价由大家负担。
下列不属于公地悲剧的是（）。

A.军备竞赛的双方都面临着一个困境——一方面军事力量不断增加，另一方面国家安全却受到越来越多的威胁

B.博弈游戏中，任何“赢”的一方都是背离游戏的，任何“输”的一方也都是背离游戏的

C.一群牧民一同在一块公共草场放牧。不少牧民都想多养羊增加个人收益，结果草场持续退化，直至无法养羊，最终导致所有牧民破产

D.有的企业把下水道污物、化学物质、放射性污染物和高温废弃物等排放到水体中，将有毒废气排放到大气中

下列因素中除哪项以外都是肾控制肾素释放的因素（）

A.血液中的血管紧张素Ⅱ

B.远曲小管中钠的浓度

C.肾动脉的灌注压

D.肾的胆碱能受体

E.肾的肾上腺素能受体