Write an MIPS program that prompts the user for a string and then parses the string exchanging the case of each character. You may assume the string comprises only lower- and upper-case alphabetic characters and spaces, with no punctuation. Change all upper-case letters to lower case and all lower-case letters to upper case. For example, if the user enters this: The Quick BrOwn foX change it to this: tHE qUICK bRoWN FOx and print the resulting string immediately below the old (input) string.