反应性系数 reactivity feedback
参考答案：
由反应性引起的反应堆某些参数（如功率、温度、压力或空泡份额）的变化对反应性的影响。
根据句意及首字母提示，写出单词。
1. There are many people in the supermarket. It's too c ____
2. Traveling by train is the most c ____ way.
3. Lucy lives f_____ from school, so she has to go to school by bus.
4. It's the best way to g____ to school by bike.
5.M ___ than 50 teachers will come here tomorrow.
男性，70岁。高血压病已20余年，未用药，血压一直持续在190／110mmHg，，在当地医院服用降压药物，2d后血压降至100／60mmHg。病人出现头晕，头晕原因可能是（）。
A.症状未改善
B.出现脑供血不足
C.诱发肾功能不全
D.诱发脑溢血
E.诱发冠状动脉痉挛
