<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title> using an external PHP </title> <meta charset="utf-8" /> <?php require_once("square.php"); ?> <link href="http://users.humboldt.edu/smtuttle/styles/normalize.css" type="text/css" rel="stylesheet" /> </head> <body> <h1> using an external PHP </h1> <?php $name = "Snoopy"; $dog = "Caesar"; "$name".'$dog' ?> <p> The square of 13 is <?= square(13) ?> </p> <p> <?= "$name".'$dog' ?> </p> <?php require_once("328footer.txt"); ?>