As a monomial, the number 3 has what degree?

The number "3" alone has the degree of 0.

Step-by-step explanation:

This is because when looking at algebraic expression, we look at the exponent of the highest variable. In this case there isn't one. This is the same

as saying a degree of 0, because a variable to the power of zero (unless it has the value of 0) is 1.