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

Q: Birds begin dying of fowl cholera _ to nine days after exposed to the virus.

A: four
****
Q: Phosphates are made of _ phosphorus atom surrounded by four oxygen atoms.

A: one
****
Q: Lions spend much of their time resting and are active only about _ hours every day.

A:
four
****