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

[Q]: Monarch caterpillars have _ pairs of tentacles.
[A]: two


[Q]: Trees can also be air layered but air layering usually takes four to _ months to be successful.
[A]: six


[Q]: Normal seawater contains _ hundred eighty milligrams of salt per liter .
[A]:
three