Tks for your advice.
0,15,30,45 7-22 * * mon-fri
1. whether create a file /usr/lib/sa/sar1 and place this line on it. Then activate the file.
How to make it run each time with following options?
$ /usr/lib/sa/sar1 sart/stop/restart
2) can "mon-fri" be replaced with "1-5" (without quote)?