企业提供给消费者的维修、保证等服务属于（）层次。A、形式产品 B、延伸产品 C、核心产品

下图中的甲图为典型的细胞核及其周围部分结构示意图；乙图为有丝分裂过程中一个细胞核中DNA含量变化曲线。请据图回答：

(1)假设甲图代表的细胞处在细胞周期中，则甲图代表的细胞相当于乙图的______区间，此时______(细胞器)活动增强；若甲图细胞中4和5结构消失，则开始消失的时间相当于乙图的________区间。

(2)甲图所示结构是否来自细菌？简述理由。____________________________________。

目前，在商业银行的全部资金来源中占最大比例的是( )。

A．负债

B．存款

C．自有资本

D．借款

平稳行驶着的车厢里挂着一小球，突然小球向列车行驶的正前方摆动，这表明列车正在（　　）

A．匀速直线运动

B．加速运动

C．减速运动

D．转弯

阅读理解。

     The day my boyfriend fell to his death,it started to snow,just like any November day,just like the

bottom hadn't fallen out of my world when he freefell off the roof. His body. when I found it,was lightly

covered with snow. It snowed almost every day for the next four months,while I sat on the couch and

watched it pile up. One morning,I shuffled downstairs and was surprised to see a snowplow clearing

my driveway and the bent back of a woman shoveling(铲)my walk. I dropped to my knees,crawled

through the living room. and back upstairs so those good people would not see me. I was embarrassed.

My first thought was, how would I ever repay them? I didn't have the strength to brush my hair let alone

shovel someone's walk.

     Before Jon's death,I took pride in the fact that I rarely asked for help or favors. I defined myself by

my competence and independence. So who was I if I was no longer capable and busy?How could I

respect myself if all I did was sit on the couch every day and watch the snow fall?

     Learning how to receive the love and support that came my way wash't easy. Friends cooked for

me and 1 cried because I eouldn't even help them set the table. "I'm not usually this lazy," I wept. Finally,

my friend Kathy sat down with me and said,"Mary,cooking for you is not a chore. I love you and I want

to do it. It makes me feel good to be able to do something for you. "

     Over and over,I heard similar emotions from the people who supported me during those dark days.

One very wise man told me,"You are not doing nothing. Being fully open to your sorrow may be the

hardest work you will ever do. "

     I am not the person I once wfls,but in many ways I have changed for the better. The fabric of my life

is now woven with gratitude and humility. I have been surprised to. learn that there is incredible freedom

that comes from facing one's worst fear and walking away whole. I believe there is strength in surrender.

1. Which of the following is true according to the passage?

A. The writer's boyfriend died when he fell off the roof he was repairing.

B. The writer had been busy with her life before.

C. The writer recovered from her sorrow quickly with his friend's help.

D. The day her boyfriend died,it was snowing heavily.

2. We can describe the writer before her boyfriend died as the following except      .

A. hard-working      

B. independent      

C. smart        

D. capable

3. The underlined word"shuffled"in Paragraph 1 probably means      .

A. stepped steadily      

B. dragged slowly

C. walked swiftly        

D. slipped sadly

4. We can infer from the passage that      .

A. the writer found her boy friend immediately he fell off the roof

B. the writer became more strong-willed after Jon's death

C. all the people around the writer were friendly and supported her

D. before Jon's death,the writer never asked others for help

5. The writer wrote the passage to      .

A. share her sad story with us

B. express her guilty conscience to the people who helped her

C. show her gratitude to the people who love and support her

D. tell us the changes she has made because of her boyfriend's death

下列氨基酸中，属于含硫氨基酸的是（）。

A．缬氨酸

B．丝氨酸

C．蛋氨酸

D．酪氨酸

E．色氨酸