Premise: 'You're not worried at all?' I asked.

Hypothesis: Aren't you worried?
Answer: yes

Premise: They are equally direct in their dealings with visitors, too, so don't expect a shy Jamaican smile as you walk by.

Hypothesis: Do not expect a shy Jamaican smile when you walk by.
Answer: yes

Premise: For the sensitivity test calculation for residential visibility, the McClelland, et al.

Hypothesis: There is a calculation to use for testing residential visibility in drinking water.
Answer: it is not possible to tell

Premise: Sewn up in oilskin.

Hypothesis: Sewed up the linen.
Answer: no