If $n(A)=2$ and the total number of possible relations from set $A$ to set $B$ is $1024$,then $n(B)$ is:

$A$ relation $R$ is defined from $\{2, 3, 4, 5\}$ to $\{3, 6, 7, 10\}$ by $xRy \iff x$ is relatively prime to $y$. Then the domain of $R$ is

The figure shows a relation between the sets $P$ and $Q$. Write this relation in roster form. What is its domain and range?

$R$ is a relation from $\{11, 12, 13\}$ to $\{8, 10, 12\}$ defined by $y = x - 3$. Then ${R^{ - 1}}$ is

If $A = \{(a, b) : 4a = 5b; a, b \in \{1, 2, 3, \dots, 30\}\}$,then the number of such ordered pairs $(a, b)$ is

The number of elements in the relation $R = \{(x, y) : 4x^{2} + y^{2} < 52, x, y \in Z\}$ is