How many strings will be added to the string pool upon execution of the following code block?public static void main$($String$[]$ args$)\{$

String str $=$ "Hello There!";

String mtr $=$ "Hello" $+""+$ "There" $+"!"$;

String dtr $=$ "Hello $"+$ "There" $+"!"$;

String gtr $=$ "Hello There" $+"!"$;

$\}$