What is the meaning of "là" in expressions like
- à ce moment-là,
- à ce niveau-là, ... ?
"Là" is an adverb. It's used for time and place.
But be carefull with the article "la" without accent
EDIT: I would like to add that "-là" is used to show that there is a distance compared to use "-ci". For exemple, "ces jours-ci" means they are closer than "ces jours-là". You can find a better explanation here: « voici » versus « voilà »