Relations and their Representation

A type of representation that represents a relation is

There are two sets a and b and $A\times B$ contains $6$ Elements of three elements of $A\times B$ as.

$\left(5,6\right), \left(2,9\right) \& \left(6,8\right)$ Then which one is not the elements of $\left(A\times B\right).$

Which of the following represents a relation in set notation?

Which of the following represents a relation in set theory?

Let $A=\left\{u, v, w, z\right\}$ and $B=\{3, 5\}$$,$ then the number of relations from $A$ to $B$ is

Let $A=\{x, y, z\}$ and $B=\{a, b, c, d\}$. Which one of the following is not a relation from $A$ to $B$?