#include using namespace std;//Return true if c is a letter (from 'a' to 'z' or 'A' to 'Z').//Don't use more than 70 characters implementing the body of this function. bool is Letter(char c){//return(((C>='A' && c='a' && c using namespace std;//Return true if c is a letter (from 'a' to 'z' or 'A' to 'Z').//Don't use more than 70 characters implementing the body of this function. bool is Letter(char c){//return(((C>='A' && c='a' && c