Premise:
"If, for example, there were no benefits of reducing PM concentrations below the proposed PM2."
Hypothesis: To give an example, if lowering PM concentrations below the suggested PM2 provided no benefits.

yes

Premise:
"and sometimes you'll get it on the first try i mean it's just"
Hypothesis: You may get it on the first try.

yes

Premise:
"As the front door swung back on its hinges, protesting loudly, Julius struck a match and examined the floor carefully."
Hypothesis: Julius' eyes still took a moment to adjust even after the match was lit.
it is not possible to tell