First one states they are standing so they can't be sitting down as well.
The question and answer are below.
Given the sentence "Several people are standing around a mechanical device of some type during a demonstration." is it true that "The people are all sitting down."?
no

Two dogs sitting next to a bicycle does not necessarily mean that the dogs are doing a good job of KEEPING THINGS SAFE.
The question and answer are below.
Premise: "Two white dogs are looking out into the street and are sitting next to a white bicycle."
Hypothesis: "Canine lookout does a good job keeping things safe."
Is the hypothesis entailed by the premise?
Options:
- yes
- it is not possible to tell
- no
it is not possible to tell

A lady playing a cello with a green tuba player in front of her does not imply they are good friends.
The question and answer are below.
If "A lady playing a cello wearing a gold skirt with a green tuba player in front of her." does that mean that "The tuba player and cello player are good friends."?
Options:
- yes
- it is not possible to tell
- no
it is not possible to tell