Which of the following commands can an operator use to view disk performance details?（） topas -D。 topas -R。 topas -C。 topas -d。
下列（）插座接线符合要求。 单相两孔插座，面对插座的右孔或上孔与相线连接，左孔或下孔与零线连接。 单相三孔插座，面对插座的右孔与相线连接，左孔与零线连接。 三相四孔及三相五孔插座的接地（PE.或接零（PEN）线接在下孔。 同一场所的三相插座，接线的相序一致。 同一场所的三相插座，接线的相序可以不一致。
You perform the following activities during the database upgrade from Oracle Database 10g to Oracle Database 11g: 1. Capture plans for a SQL workload into a SQL Tuning Set (STS) before upgrade. 2. Load these plans from the STS into the SQL plan baseline immediately after the upgrade. What is the reason for performing these activities? （） to minimize plan regression due to the use of a new optimizer version。 to completely avoid the use of new plans generated by a new optimizer version。 to prevent plan capturing when the SQL statement is executed after the database upgrade。 to keep the plan in the plan history so that it can be used when the older version of the optimizer is used。
一个城市的总人口为2500万，其包含5个城区，每个城区的人口大约在500万左右，计划进行一项抽样调查，经计算可知对该城市总人口进行推断的样本量为n。如果还想分别对5个城区的人口进行精确地推断，则样本量应该是（）。 n。 5n。 3n。 不能确定。
Companycom wants to apply a PTF to the p5 590 system. After doing a preview install, the output shows there is insufficient space in the /usr filesystem. The root volume group has no available physical partitions left. They do not want to add additional disk drives to the system, but have a jfs2 filesystem that is only 8% used. What could they do to utilize space in the jfs2 filesystem to apply this PTF?（） Backup the filesystem and recreate smaller。 Use the chfs to reduce the filesystem size。 Use cplv to copy filesystem to smaller size。 Use migratepv to copy filesystem to smaller size。
During reboot， the system hangs with an LED 0554 message that means， "The boot device could not be opened or a read failed."
Which of the following recovery procedures should be taken （）
