<SCRIPT>

var question = "What is 10 + 10?";
var answer = 20;

var correct = '<IMG SRC="correct.gif">';
var incorrec = '<IMG SRC="incorrec.gif">';

var response = prompt(question, "0");

var output = (response == answer) ? correct : incorrec;

</SCRIPT>

<BODY>

<SCRIPT>

document.write(output);

</SCRIPT>