Which statements are correct regarding message thresholds? $($choose two$)$

Thresholds are used to limit the number of exception message occurrences generated by a plan.

If a message doesn't appear because of a threshold, that means that the problem no longer exists.

Messages below thresholds are still generated $-$ they're just not displayed.

A threshold example is $-$ only generate messages about overloaded resources if required hours are more than $90\%$ of capacity