In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Tapirs have hoofed toes, with four toes on the front feet and _ toes on the hind feet.

Answer: three


Question: Human sperm comes in _ varieties, mixed.

Answer: three


Question: Ultraviolet radiation comes from sunlight, which contains _ forms of radiation.

Answer:
three