Choose the appropriate function declaration for the user-defined function is_leap(). Assume that, if not otherwise defined, the is_leap function uses the year 2000 as a default value:
{
$is_leap = (!($year %4) && (($year % 100) ||
!($year % 400)));
return $is_leap;
}
var_dump(is_leap(1987)); /* Displays false /
var_dump(is_leap()); / Displays true */