Write a function with type:
tris : 'a * 'a * 'a * 'a -> boolsuch that tris (a,b,c,d) is true iff at least three elements of the quadruple (a,b,c,d) are equal.
Then, test the function through a function with type:
hand : unit -> int * int * int * intwhich generates a random quadruple of elements in the range 1..10.