Which of the following type of lamp is used for heating a fuser？（） A: Xenon B: Halogen C: Incandescent D: Light Emitting Diode

Linux系统中，以下哪些命令可以查看一个文件是否有进程在使用？（） A: file B: lsof C: fuser D: stat

A system administrator is attempting to unmount filesystem /dev/data and receives the following message：   umount： 0506-349 Cannot unmount /dev/data： The requested resource is busy.   Which of the following commands can be used to determine which process has open references within the filesystem？（） A: lsfs B: topas C: fuser D: mount