Answer
$\text{Domain:}\;\{-2,-1,0,1,2\}$
$\text{Range:}\;\{0,1,4\}$
$\text{Yes, this relation is a function.}$
Work Step by Step
The domain of a relation is the set of $x$ values for that function. In this relation, the set of $x$ values is $\{-2,-1,0,1,2\}$. The range of a relation is the set of $y$ values for that relation. In this relation the set of $y$ values is $\{0,1,4\}$. A relation is a function if each $x$ value has only one unique $y$ value. Since there are not elements of the domain that are repeated with different elements of the range, this relation is a function.