The number of distinct relations on a set $A$ is given by $2^{n^2}$, where $n$ is the number of elements in the set. Here, $A = \{1, 2, 3\}$, so $n = 3$.
Thus, the number of relations is: \[ \text{Number of relations} = 2^{n^2} = 2^{3^2} = 2^9 = 512 \]
Let \( S = \{p_1, p_2, \dots, p_{10}\} \) be the set of the first ten prime numbers. Let \( A = S \cup P \), where \( P \) is the set of all possible products of distinct elements of \( S \). Then the number of all ordered pairs \( (x, y) \), where \( x \in S \), \( y \in A \), and \( x \) divides \( y \), is _________.
For a two-port network to be reciprocal, it is necessary that ……..