$4$ a$)$

Identify the output that the following Java code produces and

explain your reasoning clearly.

public class Recursion

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

system.out.println $($mystery $("$Start$"))$;

$\}$

public static String mystery$($String input$)\{$

if $($input$.$ length $()>10)\{$

return "Complete";

$\}$

System.out.println $("$Running$...")$;

return $($mystery $($input$+"$x$")+"$OK$")$;

$\}$

$\}$

b$)$ Identify the output that the following Java code produces and $[7$ marks$]$

explain your reasoning clearly.

public class BitManipulation

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

System.out.println $((((7$&;

$\}$

$\}$

c$)$ Show how the following numbers would be sorted by mergesort.

State the Big $O$ complexity of mergesort and explain why it is

more efficient than bubble sort.

$84,25,83,96,36,10,57,29$