In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

Q: Butterflies have _ pair of legs - each divided into five parts.

A: three
****
Q: Diatoms are in _ shells and make the water brown.

A: two
****
Q: Incomplete metamorphosis takes place with nymphs hatching in about _ months.

A:
four
****