If $f,g$ are non-zero polynomials and $f$ divides $g$, then $\partial f \leq \partial g$.

Question

Mark the following true or false. (Here 'polynomial' means 'polynomial over $\mathbb{C}$'.)

1. If $f,g$ are non-zero polynomials and $f$ divides $g$, then $\partial f \leq \partial g$.

$\textbf{True.}$

2. Every irreducible polynomial has prime degree.

$\textbf{True.}$

3. If a polynomial $f$ has integer coefficients and is irreducible over $\mathbb{Z}$, then it is irreducible over $\mathbb{R}$.

$\textbf{True.}$ Since $\mathbb{Z} \subseteq \mathbb{R}$, then we can say that a polynomial, $f$ is irreducible over $\mathbb{R}$, if it is irreducible over $\mathbb{Z}$.

So I need to response to each of these questions with $3$ sentences or less. How would I do this for (1) and (2)? Also is what I have for number (3) enough or correct?