<html>
<head>
<script>
function displayResult()
{
document.getElementById("div1").style.lineHeight="2";
}
</script>
</head>
<body>
<div id="div1">
This is some text. This is some text. This is some text.
This is some text. This is some text. This is some text.
This is some text. This is some text. This is some text.
This is some text. This is some text. This is some text.
</div>
<br>
<button type="button" onclick="displayResult()">Change line height</button>
</body>
</html>