06. How do you set IE compatibility mode?

By using http-equiv=X-UA-Compatible meta tag with content IE=edge
IE=edge mode tells Internet Explorer to display content in highest mode available

Some more information.

Example:

<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta name="description" content="I am a web page with description"> 
  <title>Home Page</title>
</head>
<body>
  
</body>
</html>