linux - Merge two crontab entries into a single entry

Question

In my crontab file I have two entries

00 13 * * * DISPLAY=:0.0 /home/noob/.scripts/backup.sh 
00 21 * * * DISPLAY=:0.0 /home/noob/.scripts/backup.sh

Now can I write a single entry which executes the backup.sh file @ 1:00PM and 9:00PM.

Answer 1

00 13,21 * * * DISPLAY=:0.0 /home/noob/.scripts/backup.sh