If $A = \{ a,\,b\} ,\,B = \{ c,\,d\} ,\,C = \{ d,\,e\} ,\,$ then $\{ (a,\,c),\,(a,\,d),\,(a,\,e),\,(b,\,c),\,(b,\,d),\,(b,\,e)\} $ is equal to

If $A$ and $B$ are two sets, then $A × B = B × A$ iff

If the set $A$ has $3$ elements and the set $B=\{3,4,5\},$ then find the number of elements in $( A \times B ).$

$A = \{1,2,3,4......100\}, B = \{51,52,53,...,180\}$, then number of elements in $(A \times B) \cap  (B \times A)$ is

If $A=\{-1,1\},$ find $A \times A \times A.$

If two sets $A$ and $B$ are having $99$ elements in common, then the number of elements common to each of the sets $A \times B$ and $B \times A$ are