Answer No : 10 : 
<html>
<head>
	<title>Lionet Computer Training institute</title>
</head>
<body>
	<h2 align="center">RED</h2>

	<hr style=" background: red; height: 20px; border: none;">

	<h2 align="center">ORANGE</h2>

	<hr style=" background: orange; height: 20px; border: none;">

	<h2 align="center">YELLOW</h2>

	<hr style=" background: yellow; height: 20px; border: none;">

	<h2 align="center">GREEN</h2>

	<hr style=" background: green; height: 20px; border: none;">

	<h2 align="center">BLUE</h2>

	<hr style=" background: blue; height: 20px; border: none;">

	<h2 align="center">INDIGO</h2>

	<hr style=" background: indigo; height: 20px; border: none;">

	<h2 align="center">VIOLET</h2>

	<hr style=" background: violet; height: 20px; border: none;">

</body>
</html>
Output: