A man has 3 sons,An engineer asked their ages,He said"When you multiply the ages of my sons,the result will be 36"Still,the engineer couldn't tell tHeir ages.So the man gave the engineer another clue,"If you add their ages,it will be the same as the number of our apartment,".But even though the enginwer knows the number of the apartment,he still couldnt determine their ages.So the man gave him the last hint,"My eldest son's bedroom is in the second floor."What are their ages?