I have written a new script. I have got a bit confused...The code is below.
What will be printed on screen?

<?php

function multiply($input1, $input2=5){
    $number1 = 10;
    $number2 = 20;
    return $number1 * $number2;
}

function add($input1, $input2=1){
    return $input1 + $input2;
}

function new_math($input1, $input2){
    return $input1 * ($input2 * $input2);
}

$number0 = 0;
$number1 = 1;
$number2 = 2;
$number3 = 3;

$p = '<p>';
$pc = '</p>';
$br = '<br />';

$newnumber = $number1.$number2;
$newnumber2 = add($number1,$number2);
$newnumber3 = $number1.$number0 - $number3 - $number2;

echo $p.multiply($newnumber).$pc;
echo $p.add($newnumber2).$pc;

echo $p;
for($i=1;$i<=10;$i++){
    echo new_math($i,$newnumber3).$br;
}
echo $pc;

?>

200

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