Given the rationale, provide a reasonable question and answer. Step-by-step reasoning process: A skier cannot both go down and up the mountain at the same time.
 The question and answer:
Premise: "A skier going goes down the mountain."
Based on this premise, can we conclude that the hypothesis "The skier climbs up the mountain." is true?
Options:
- yes
- it is not possible to tell
- no
The answer is no