Answer
$ a.\quad$ Not a function
$ b.\quad$ none
Work Step by Step
$ a.\quad$
Apply the vertical line test:
If it is possible for a vertical line to cross a graph more than once,
then the graph is not the graph of a function.
The graph fails the test, as the vertical line $x=-2$
crosses it in infinitely many points.
Not a function.
$b.$
- does not apply - not a function.