<!DOCTYPE html>
<html lang="en-US">
<head>
<style>
#point:after{
content:"\0222A";
}
</style>
</head>
<body>
<p>Union using Hexa Decimal: ∪</p>
<p>Union using HTML Code: ∪</p>
<p>Union using HTML Entity: ∪</p>
<p id="point">Union using CSS Entity: </p>
</body>
</html>