根据照度平方反比定律，当距离增大到为原有值的三倍时，其照度即减少到（）
A.1/2
B.1／6
C.1/8
D.1/4
E.1/9
参考答案：E
There _____ be any difficulty in passing the road test since you have practiced a lot in the driving school. [ ]
A. shan't
B. shouldn't
C. mustn't
D. needn't
吸附分离装置开车进油时的注意事项是（）。
A、吸附塔走旁路
B、所有可投用的测量、控制仪表均需参加试运
C、注意除禁区以外的所有的管线，包括临时开工管线必须要参加全流程的循环
D、吸附分离进料、解吸剂过滤器要安装开工滤芯
