Premise: A group of climbers ascends a narrow , snowy mountain ridge .
Correct statement: It is certain that people climb up a mountain during the day time .
Incorrect statement: It is unlikely that people climb up a mountain during the day time .
Correct statement: We doubt that a family is climbing a snow mountain .
Incorrect statement: It is certain that a family is climbing a snow mountain .
Correct statement: It is impossible that the climbers are on Mt. Everest .
Incorrect statement: It is almost certain that the climbers are on Mt. Everest .
Correct statement: We believe that some climbers high up on a mountain .
Incorrect statement: It is unlikely that some climbers high up on a mountain .
Correct statement: Chances are about even that a group of climbers makes their way to a rest stop on a mountain ridge .
Incorrect statement: It is impossible that a group of climbers makes their way to a rest stop on a mountain ridge .