Premise:
"The number of studies that have demonstrated effects either with volunteer or randomized participants is modest but increasing, and the effects range from minimal to very sizeable reduction in risks that have significant public health importance."
Hypothesis: There haven't been any studies on this topic and there don't seem to be any public health implications.

no

Premise:
"Of course he had seen very little of Hunt Rennie at the Stronghold; his father had ridden south on patrol with his own private posse shortly after his own arrival there."
Hypothesis: At the Stronghold, he saw is father constantly because he was always there.

no

Premise:
"It will also improve visibility over much of the country, particularly the scenic vistas in national parks such the Grand Canyon."
Hypothesis: The Grand Canyon will see an improvement in visibility thanks to it.
yes