public class A

private int private int x $=1$: y $=2$

public class B extends A $\{$

private int x $=300$ private int z $=400$

public int m$\{$

public int m $()\{$

return x $+$ y

return super.m m $()+$z;

$\}$

public int x$(\{$

return x;

public int x$20)\{$ return $2$ this.x$($;

$\}$

$\}$

Consider the following code:

A a$1=$ newA $()$;

A a$2=$ newB$()$ ; For each expression below, write the type of the expression. Write "Unknown" if it is impossible to determine the type from the code fragment given. Write "Illegal" if the expression is never allowed$$in$$Java$.$

B a$3=$ new B$()$;