采用综合重合闸装置后，在发生单相接地短路时，断路器的动作状态是（）。 只跳故障相。 跳任一相。 跳三相。
You execute the following command to change the status of the SALES tablespace： SQL> ALTER TABLESPACE sales OFFLINE； Which statements describe the effect of the command（） The tablespace would require recovery to go back online.。 A checkpoint is taken on all data files that are associated with the SALES tablespace.。 The sessions that subsequently try to access the objects in the SALES tablespace receive an error.。 The new status of the SALES tablespace is recorded in the control file when the database instance is closed.。
对高温、高压锅炉，烘炉期间的上水应采取（）。 一般工业水。 除盐水。 软化水。
You have lost datafile 4 from your database. Which is typically the fastest way to restore your database? （） Restore and recover the datafile. 。 Restore and recover the tablespace. 。 Restore and recover the database. 。 Restore and recover the control file. 。 Restore and recover the parameter file.。
公园
我国法定计量单位中共有（）个基本单位。
