QUESTION $5$

What is wrong with the following code:

class Circle$\{$

double radius;

double diam;

double area$()\{$ return radius $*$ radius $\{$:${?}^{**}3\mathrm{.}24$;$\}$

void diameter$()\{$ diam$=$ radius $\{$:${?}^{**}2$;$\}$

public static void main$($String$[]$ args$)\{$

Circle $c=$ new Circle$()$;

c$.$radius $=2\mathrm{.}1$;

c$.$diameter$()$;

System.out.println$($c$.$area$())$;

$\}$

$\}$

A$.$ radius and diam are dependent, so one of them should me a method.

B$.$ The method diameter should return double.

C$.$ radius should be private.

D$.$ The class has no constructor

QUESTION $6$

What is the output of the following program

class X$\{$

final int $a$;

$x()\{a=5$;$\}$

public static void main$($String$[]$ args$)\{$

$xx=$newx$()$;

System.out.println$("$X$.$a $="+$ x$.$a$)$;

$\}$

$\}$

A$.$ X$.a=5$;

B$.$ X$.a=0$;

C$.$ The program has error because a is not static.

D$.$ The program has error because a should be initialized when it is declared.