铁路运输价格管理遵循的原则有（）。 A.社会平均成本 B.市场供求状况 C.

I have known Ting for a long time. She was a friend of mine in high school. Ting used to see me as her best friend in my class because, as she said , it was easy to be friends with me . Therefore ,when we had time in school,she often came to me and we would talk about many things. Though I didn’t have special feelings about this friend, I was fine with this because I didn’t see the reason why I should say “no” to a friend I didn’t hate.

But there was a while when she came to me, and usually said nothing meaningful. I started to feel tired and then tried not to meet her. After that she never came to me. Though guilty, I started to feel free about my life and never thought of anything about her feeling.

After a month or two, I heard from other friends that Ting’s father had passed away six months before. I was so shocked! Then I suddenly realized why Ting had often come to me but said nothing special. She needed my company (陪伴). I felt so bad about myself that I went to find her the next day. But I only found that she had moved away to another place.

At that time, I found myself so selfish that I only thought of myself but didn’t even try to ask a friend what happened in her life.

小题1:“I was fine with this because ….” What does “this” mean here?

A．Ting’s coming to the writer.

B．The things Ting said.

C．The writer’s own feeling.

D．Ting is easy to be with.小题2:What did the writer think of Ting in the beginning?

A．The writer didn’t like Ting.

B．The writer felt bored with Ting.

C．Ting was considered the best friend.

D．The writer had no special feelings about Ting.小题3:What is the story about?

A．About happiness.

B．About friends.

C．About the meaning of life.

D．About how to be with friends.小题4:Which is NOT true according to the passage?       

A．Ting is not the writer’s best friend.

B．Ting told the writer that her father died.

C．The writer didn’t care enough about her friend.

D．The writer is sorry for what she has done to her friend.

若x²ⁿ=3，则x⁴ⁿ=______．

以下对后戗的规定正确的是（）。

A、坡度不应陡于原有堤坡

B、坡度小于1：1

C、高度不超过最高洪水位

D、厚度视土堤滑坡、坍塌程度而定

E、一定和原渠堤同高

当气体线速度增大，滑落系数将（）。

A、增大趋近于1

B、减小趋近于0

C、维持不变

D、减小趋近于1

肺泡上皮细胞包括（），（）。