Premise:
"With time, it would have been easy enough, but there was no time for trial and error."
Hypothesis: Time was about to run out and trial and error proved inefficient before.

it is not possible to tell

Premise:
"Restaurants serve lunch from 1:00 to 3:00 p.m. and dinner from about 8:00 to 11:00 p.m."
Hypothesis: Eating establishments give out lunch between the hours of 1:00 to 3:00 p.m. and then dinner at about 8:00 to 11:00 p.m.

yes

Premise:
"If our hypothetical couple were in the highest income tax bracket and their contributions represented all new saving, their $4,000 deduction would cost the government $1,584 and add $2,416 to national saving."
Hypothesis: If our hypothetical couple were in the highest income tax bracket and their contributions represented all new saving, their $4,000 deduction would cost the public $75 per household.
it is not possible to tell