To enable faster incremental backups, you enabled block change tracking for the database.Which two statements are true about the block change tracking file?（） [" Multiple change tracking files can be created for a database."," The change tracking file must be created after the first level 0 backup."," RMAN does not support backup and recovery of the change tracking file."," The database clears the change tracking file and starts tracking changes again, after whole database restore and recovery operations."]
热采井机械采油的中期阶段，原油温度、动液面下降，产量较高，含水很低，抽油机（）因粘度上升而上升。 ["电流","泵效","回压","负荷"]
从权力的性质上，一般把行政领导权力分为权力性影响力和（）。
教师在教学中，要从课程计划、学科课程标准的统一要求出发，面向全体学生，同时又要根据学生的个别差异，有的放矢地进行教学。这一原则是（） ["循序渐进原则","因材施教原则","直观性原则","巩固性原则"]
碱液中为什么要控制NaCl的含量？
简述管理哲学和一般哲学的关系。
