提高功率因数有哪些方法？

A. 打开门窗通风，在屋内喷洒杀虫剂
B. 在居住区的周围喷洒杀虫剂
C. 关闭门窗，在屋内喷洒杀虫剂，睡眠时使用蚊帐
D. 使用电驱蚊器

A. 1km
B. 2km
C. 3km
D. 4km

A file system cannot be mounted on a directory containing data.
B. Mounting a file system on a mount point containing data will delete the data.
C. Mounting a file system on a amount point containing data will make the data temporarily inaccessible.
D. A systems administrator must manually create an empty directory prior to mounting an AIX JF