Question

Saying a whale and a lion are both mammals is a ________

however, the fact that a lion lives on land and a whale lives in the ocean is an example of
_______

Answer 1

1. That is an opinion, giving its a object and its been proven and supported by multiple different sources and it's a statement said by someone else.
2. That's a fact knowing its a touchable object in and force in reality(you can also see it)

Answer 2

Similarity or comparison, second blank difference/ contrast.
Hope this helps!