In Prolog, define a predicate mergesort(In,Out) that makes a sorted version of a list In of numbers and unifies that result with Out. Your predicate should use a merge-sort algorithm. SWI-Prolog has a predefined predicated called sort, and another called msort, that implement variations of merge sort. Don't use those, but choose another name for yours.

DON'T USE PREDEFINED PREDICATES SORT OR MSORT