Answer
$\text{Domain:}\;\{1,2,3\}$
$\text{Range:}\;\{4,8,10,15\}$
$\text{No, this relation is not a function.}$
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 $\{1,2,3\}$. The range of a relation is the set of $y$ values for that relation. In this relation the set of $y$ values is $\{4,8,10,15\}$. A relation is a function if each $x$ value has only one unique $y$ value. Since $2$, an element of the domain, is repeated with multiple $y$ values, this relation is not a function.
