Premise:
"One heads west to Vale do Paraiso, the other northeast to Eira de Fora."
Hypothesis: People from Eira de Fora don't generally like people from Vale do Paraiso.

it is not possible to tell

Premise:
"The sensitivity of cost to volume for a postal system can be investigated directly provided the ratio of fixed to variable costs is known by function."
Hypothesis: Postal system costs are strongly linked to volume.

it is not possible to tell

Premise:
"But once such a gun is broken, where can they get another?"
Hypothesis: Where can one purchase a replacement for a broken gun?
yes