Concerning the management of sewage treatment plant using activated sludge, which of the following is correct?（） ["the plant should be prohibited to supplying air","the plant should work at intervals","the plant should be added disinfector in time","we should check strength of activated sludge, ivory-white color is best"]
在进行时间优化时，缩短关键路线上活动时间的途径有（）。 ["A.利用平行、交叉作业缩短关键活动的时间","B.在非关键路线上赶工","C.在关键路线上赶工","D.采用新技术缩短工作时间","E.进一步压缩最短路线上的工作时间"]
秧苗移栽后由于根系受到损伤，需要5-7天时间地上部才能恢复生长，根系萌发出新根，这段时期称（）期。
500kV线路并联电抗器操作规定有哪些？
什么是抗干扰接地？
电压互感器的操作顺序如何？
