Activity 5-4 - Predefined Character Functions in cctype (ctype) In C++, we have several predefined character functions. These functions are listed below: Function Name Description Example char c, d 'a'; toupper Returns the uppercase version of the argument character. If the character is already an c = toupper(d); (a character) cout #include using namespace std; int main() chare; cout>c; if(isalpha(c)) {//check to see if it is a letter of alphabet if(isupper(e)) //check to see if it is uppercase c=tolower(e); cout