Answer:
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Explanation:
Hello!
1) Firstly, let's enlist all the coordinate, (x,y) points to visualize it better.:

2) Check the pair of sets for this function below. The Domain Set, on the left. The Range set, on the right. This Diagram shows a one to one (injective and surjective) function . Since its element of the Range is 4, then its corresponding one on the Domain set is 2.