轴封风机排气管为什么要设疏水？

往一个底面直径是10cm，高是8cm的圆柱形容器中装水，里面浸没一个底面直径6cm，高7.5cm的圆锥形铅锤，当铅锤取出后，杯里水面下降了多少厘米？

It is a strange phenomenon that some young people today think it is their parents’responsibility to earn money and_______ to spend it.

A．them

B．they

C．their

D．theirs

皮革：铁

A．有弹性的：重的

B．结实的：固定的

C．弯曲的：平滑的

D．坚韧的：坚硬的

I still remember the day when my mom said, “Let’s get you some new clothes.” You can imagine that to any little girl that would mean the world, but to me it meant the universe, because we were not very rich. After she said that, all I could think about was what kinds of clothes I would choose. To my surprise, my mom allowed me to pick out three dresses: a pink one, a blue one and a yellow one. The yellow one was my favorite.

I had a best friend named Seema, whose family was even poorer than ours. We played and studied together, and spent the best days of our childhood laughing at the silly stories we made up. I was excited to show her my three beautiful new dresses. She loved them all and was happy for me, but tearfully explained to me that her father could only afford to buy her clothes for her birthday. I felt sorry, and then did something that surprised even myself: I asked her to pick out one of my dresses for herself. To my disappointment, she picked up my favorite—the yellow one. Please remember, I was only seven years. My heart almost popped out (跳出) of my chest. But as she held it against her body, and I saw how brightly she smiled, I stopped feeling any hurt. I told her it looked lovely on her.

I’ll always remember Seema’s smile, and how at that moment nothing mattered more. When you value your friendships, nothing else matters! We’re still best friends today.

小题1:Why did the new clothes mean the universe to the author?

A．She loved dressing up more than anything else.

B．She thought they would make her more beautiful.

C．Her family was poor, and new clothes were very rare.

D．Her mother only bought her new clothes for her birthday.小题2:The author let Seema pick out one of her dresses because she wanted to _______.

A．show her pity for Seema’s family

B．show off her family’s wealth

C．make Seema become her best friend

D．exchange it with Seema’s dress小题3:When Seema chose the yellow dress, the author was disappointed because ________.

A．she was not generous

B．she didn’t expert to lose her favorite dress

C．Seema chose her favorite dress on purpose

D．Seema was careless about her feelings小题4:What can we conclude from the passage?

A．Getting a best friend means losing other things.

B．Being generous is not easy.

C．Children like sharing their favorite things.

D．Friendship is precious (珍贵的).

定量地表示颜色（表观色和物体色）的体系称（）