yes, 3 is a polynomial, a monomial, and its degree is 0 (zero)
1) Since a polynomial is defined as:
[tex]P(x)=a_nx^n+a_{n-1}x^{n-1}+....a_1x+a_0[/tex]2) Examining the number 3, we can tell the following:
[tex]3=3x^0[/tex]So, yes, 3 is a polynomial, and better classified as a monomial (for there's one single term), and the degree of this polynomial is 0