不演变为肝硬化的肝炎是A．甲型肝炎 B．乙型肝炎 C．丙型肝炎 D．丁型肝炎 E．戊

精子属于（）

A.异嗜性抗原

B.同种异体抗原

C.自身抗原

D.肿瘤抗原

E.半抗原

阅读短文，根据短文内容，从短文后的五个选项中选出能填入空白处的最佳选项。选项中有一项为多余选项。

Note-taking is a skill that can help you do well in all your schoolwork. It can make you confident when you are studying. 小题1:____________________

If your teacher writes notes on the blackboard, that's great. You can copy them or write down the most important facts of all in class. 小题2:____________________ For example, some teachers may focus on (关注) lots of dates and facts in class, but they only write the important ones on the blackboard. Other teachers may not write anything down, but they may repeat them.

Don't try to write down every word in class, or you might miss some important points. Some students really learn better with the help of these notes. 小题3: ____________________ If your teacher speaks too fast and you can't follow what he is saying, you can ask him after class.

Comparing your notes with your classmates' can be good for your learning. 小题4:____________________

Note-taking also needs organization. Keep notes for each subject in one place, so that you can find everything easily when a test comes.

Good note-taking takes time. If you decide to recopy your notes every evening, you'll surely have less time to watch TV. But you'll save time in the coming test.

已知某一换热器的总传热系数K=280W╱m2℃，逆流时的对数平均温差Δtm=120℃，逆流时的总热负荷Q=1680000W，则该换热器的传热面积A为（）。

A、0.5m2

B、5m2

C、50m2

D、500m2

淋家

量水堰法，需修筑挡水溢流堰，读取堰上水头，用（）公式计算过堰流量。

A.水力学堰流

B.流速

C.水位

D.高程