Sentence 1: The street was narrow and my spine was soon pressed against a brick wall.

Sentence 2: There was plenty of room to move around where I stood.
Is this second sentence entailed by the first?

Answer: no

Sentence 1: natural seawater of higher salinity, or hypersaline brine.

Sentence 2: Natural seawater can have varying levels of salinity.
Is this second sentence entailed by the first?

Answer: yes

Sentence 1: and be ready to cry or whatever

Sentence 2: Most people cry in this situation.
Is this second sentence entailed by the first?

Answer:
it is not possible to tell