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<!DOCTYPE html>
<html>
<body>

<img id="myImg" src="w3javascript.gif" width="100" height="132">
<br>

<button type="button" onclick="myFunction()">Change height and width of image</button>

<script>
function myFunction() {
    document.getElementById("myImg").style.height = "300px";
    document.getElementById("myImg").style.width = "300px";
}
</script>

</body>
</html>