Is this code correct?

YouthBirthday birth;
birth               = new Birthday( "Terry", 23 );

A good answer might be:

No. A reference variable for a child class (YouthBirthday) cannot be used for an object of a parent class (Birthday).

Parents can accommodate children, but children can't accommodate parents. If you find this rule hard to remember, just think of yourself and your parents:

It is OK for you to go home and stay in your parent's house for a few days, but it not OK for them to stay in your dorm room for a few days.

Now let us re-write YouthBirthday in order to show more about polymorphism. Say that you want two greeting() methods for YouthBirthday:

1. The parent's greeting() method.
   • This will be included by inheritance.
2. A method with the name of the sender as a parameter.
   • This will be an additional method---it will not override the parent's method.
   • In addition to what the parent's method does, this method will write out "How you have grown!!   Love,"   followed by the name of the sender.

// Revised version // class YouthBirthday extends Birthday { public YouthBirthday ( String r, int years ) { super ( r, years ) } // additional method---does not override parent's method public void greeting( ___________ ____________ ) { super.greeting(); System.out.println("How you have grown!!\n"); System.out.println("Love, " + ___________ + "\n" ); } }

QUESTION 11:

Fill in the missing parts.