It is important to get information about a flight from many parts of the airplane.

Yes
It could have a non sufficient engine for the size of the plane so then I put couldn’t take off

If the water vapor content stays the same and the temperature drops, then the relative humidity increases. its vise versa.if the water vapor content stats the same and the temperature rises, the relative humidity decreases. so, yes, i'd say that temperature and humidity have a strong relationship.