单项选择题 An administrator has a two-disk volume group （testvg） with one logical volume （testlv） which has just been mirrored across both disk drives. Which of the following commands can be used to turn off quorum？（）

单项选择题 An administrator has received complaints from users that an application is not available while other applications run. This application resides on an NFS mounted filesystem. Which of the following commands should be run as a reasonable first step to handle this problem？（）

单项选择题 WhichactionchangesthedefaulteditorforALLusersonthesystemfromvitoedit？（）