简述中国古代木结构建筑的优势

John gets up early from Monday to Saturday, because he must go to school before 7:30 0n weekdays (工作日) and go to the Drawing Club at 8:00.  0n Saturday mornings. He usually goes to the bookshop on Saturday afternoons, and after supper he watches TV until(直到) midnight.

He doesn't get up early on Sundays. John's parents both work on Sundays. John always watches TV after he gets up. Then he usually goes to KFC to have a hamburger and some juice for lunch. After that, he goes back home and starts to play computer games until his parents come back. He does his homework after supper. He usually has lots of weekend homework, so he must spend three hours on it. He usually goes to bed at about 11:00 p. m. on Sundays. He often complains (抱怨) he has too much homework to do.

小题1:How often does John need to get up early?

A．Every day.

B．Five days a week.

C．Only at the weekend.

D．Every day except on Sundays.小题2:What does John do on Sunday mornings?

A．He goes to have lessons.

B．He goes to a club.

C．He goes to the bookshop.

D．He watches TV.小题3:When does John do his weekend homework?

A．On Sunday evenings.

B．On Sunday mornings.

C．On Saturday evenings.

D．On Sunday afternoons.小题4:Why does John have lunch in KFC on Sundays?

A. Because he's too busy.

B. Because his parents aren't at home.

C. Because he gets up too late.

D. Because his parents have lunch in KFC.

小题5:Which of these is not right?

A．John watches TV after supper on Saturdays.

B．John doesn't exercise on Sundays.

C．John watches much TV on Sunday afternoons.

D．John goes to bed late on Saturday and Sunday evenings.

如图所示，在倾角为θ的斜面上放置一内壁光滑的凹槽A，凹槽A与斜面间的动摩擦因数μ＝，槽内紧靠右挡板处有一小物块B，它与凹槽左挡板的距离为d．A、B的质量均为m，斜面足够长．现同时由静止释放A、B，此后B与A挡板每次发生碰撞均交换速度，碰撞时间都极短．已知重力加速度为g．求：

（1）物块B从开始释放到与凹槽A发生第一次碰撞所经过的时间t₁．

（2）B与A发生第一次碰撞后，A下滑时的加速度大小a_A和发生第二次碰撞前瞬间物块B的速度大小v₂．

（3）凹槽A沿斜面下滑的总位移大小x．

用Ficoll分离人外周血淋巴细胞时离心后，细胞分布情况如下（）

A.单个核细胞沉于管底，红细胞悬浮于血浆层中，血小板分布于界面

B.血小板沉于管底，红细胞悬浮于血浆层中，单个核细胞分布于界面

C.红细胞沉于管底，血小板悬浮于血浆层中，单个核细胞分布于界面

D.单个核细胞沉于管底，血小板悬浮于血浆层中，红细胞分布于界面

E.血小板沉于管底，单个核细胞悬浮于血浆层中，红细胞分布于界面

新生儿出生体重2800g，身长50cm，面色红润，哭声响亮，一般情况好，现母乳喂养。

授乳后婴儿应取的体位是( )。

A．左侧卧位

B．右侧卧位

C．平卧位

D．头侧位

E．坐位

在常用法定计量单位换算中，（）毫米等于1000微米。

A、0.01

B、0.1

C、100

D、1