Question

No explanation required

Answer 1

Answer:  Yes it is a function.

Reason:

There are no repeated x values, so each x input leads to exactly one y output. That's why we have a function.

If we had something like (1,18) and (1,12), then the input x = 1 leading to simultaneous outputs y = 18 and y = 12 would mean we wouldn't have a function.