Explain each operation given below for a type PAIR? CLO$2($Marks $4)$ PAIR $($A with $\{$ A $==$ A $\},$ A $\backslash$times A $->$ Bool, under$1$: PAIR $->$ A$,$ under$2$: PAIR $->$ A$)$ sort Pair constants under$1,$ under$2$: Pair $->$ A uses Boolean first: Pair $->$ A second: Pair $->$ A pair: A $\backslash$times A $->$ Pair