多项选择题 You work as a database administrator for Certkiller .com. Your listener process， L1，is currently listening to three databases：CertK INDB04，Certkiller DB05 and Certkiller DB06. Using Database Configuration Assistant （DBCA） you create one more database，Certkiller DB07，and enable dynamic registration.  Which two commands of Listener Control Utility （lsnrct1） would you use to determine whether the dynamic registration occurred for the database， Certkiller DB07， with the L1 listener process？（）

单项选择题 You work as a database administrator for Certkiller .com. You are using Recovery Manager （RMAN） for backup and recovery of your database. You executed the delete command in RMAN to delete a backup of atablespace. Which statement is true in this scenario？（）

单项选择题 YouworkasadatabaseadministratorforCertkiller.com.Accordingtoyourbackupstrategy，youperformedanincrementallevel0backupofyourdatabase.Whichstatementregardingthisbackupistrue？（）