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

[Q]: Adult muskrats average one foot in length and _ pounds in weight.
[A]: three

[Q]: Porcine insulin has _ different amino acid and bovine insulin has three different amino acids.
[A]: one

[Q]: Viroids are known to cause disease in at least _ plant groups.
[A]:
six