Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.

Yellow fever begins suddenly after an incubation period of three to ____ days.
five

Most orthoptists work ____ hours a day, four or five days a week.
eight

Foxes have an average home range varying from one to ____ miles.

four