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

[EX Q]: Black widows mature in two to _ months.
[EX A]: four

[EX Q]: Binary distillation separates _ chemicals.
[EX A]: two

[EX Q]: External radiation is given in divided doses to the pelvis five days a week for _ weeks.
[EX A]:
five