PLEASE HELP!! In Scheme language using Dr. Racket

Write a function/series of functions called explode that will take a string as a parameter and return a list containing the characters of the string. > (explode "Hello") '("H" "e" "1" "1" "o") I) Create a function/series of functions called implode that will take a list as a parameter and return a string containing the list elements. (Double this is very much a re-write of H) > (implode '("H" "e" "1" "1" "o")) "Hello