Find the domain and range of the function represented by the graph.

The graph is a filled-in point at ordered pair negative 4 comma negative 1, a line segment from ordered pair negative 4 comma negative 1 to ordered pair 0 comma 3, a line segment from ordered pair 0 comma 3 to ordered pair 2 comma 3, a line segment from ordered pair 2 comma 3 to ordered pair 3 comma 4, and a filled-in point at ordered pair 3 comma 4.
The domain is
$\le x\le$
.

The range is
$\le y\le$
.