22. [10 points] Write an ML recursive function listProduct of type int list -> int to calculate the product of all elements in a list. 23. [10 points] Write an ML function min of type int list -int that returns the smallest element of a list of integers. Hint: write a helper function minhelper that takes as a second parameter the smallest element seen so far. Then you can complete the exercise by defining fun min x = mnhelper (tl x, hd x)