In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Germs have _ means of locomotion execpt to attach themselves to particles of dust.

Answer: no

Question: Human sperm comes in _ varieties, mixed.

Answer: three

Question: Pups are unable to swim or find food until seven to _ weeks old or until the ice melts .

Answer:
eight