<?php
$mars = array ('How big is Mars?', 'How many moons does Mars have?', 'How far away is Mars?', 'What is the highest point on Mars?');
$jupiter = array ('How big is Jupiter?', 'How many moons does Jupiter have?', 'How far away is Jupiter?', 'What is the highest point on Jupiter?');
$earth = array ('How big is Earth?', 'How many moons does Earth have?', 'How far away is Earth?', 'What is the highest point on Earth?');
$sun = array ('How big is the Sun?', 'How many moons does the Sun have?', 'How far away is the Sun?', 'What is the highest point on the Sun?');
 
$all = array($mars, $jupiter, $earth, $sun);
shuffle($all);
 
function createList($a)
{
echo "<ul>"; 
  $count = 1;
 
foreach ($a as $array) 
    {
    $questions = count($array);
    $idquestion = rand(0, $questions-1);
    echo "<li>" . $array[$idquestion]  . "</li>";
          if ($count++ >= 3) {
        break;
    }
    }
echo "</ul>";
}
 
createList($all);

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