Ask the user to enter their age and id. Id must be unique. If Id already exists show appropriate message. If Id is unique add the data to a file. Give user three option add, modify or delete. The user can delete the existing record by entering the unique Id, if Id matches to the information in a file delete that record from a file. If user chooses to modify they can modify the age, ask the user for id and modify the age entered by the user. Update the existing file, and sort the file. This all should be done in java