Answer/Step-by-step explanation:
3. Function: NO
Justification: there will be more than one y-value/output related to one x-value/input.
4. Function: YES
Justification: There are exactly one y-value/output related to each input/x-value in the relation.
5. Function: YES
Justification: each x-value/input is mapped to exactly one y-value/output. No input value is mapped to more than one output value.