What will be the output of the following PHP code?

<?php
    function a()
    {
        function b()
        {
            echo 'I am b';
        }
        echo 'I am a';
    }
    b();
    a();
?>

A. function { function body } B. data type functionName(parameters) { function body } C. functionName(parameters) { function body } D. function fumctionName(parameters) { function body }

A. PHP 4 B. PHP 5 C. PHP 5.3 D. PHP 6

<?php
function calc($price, $tax)	
{
    $total = $price + $tax;
}
$pricetag = 15;
$taxtag = 3;
calc($pricetag, $taxtag);	
?>

A. Call By Value B. Call By Reference C. Default Argument Value D. Type Hinting

<?php
function calc($price, $tax="")
{
    $total = $price + ($price * $tax);
    echo "$total"; 
}
calc(42);	
?>

A. Error B. 0 C. 42 D. 84