Set the font size of the p element.

<html>
<body>
<h3>Eye Exam</h3>
<p style="font-size:24px;">E</p>
<p style="font-size:12px;">F P</p>
<p style="font-size:8px;"> T O Z</p>
</body>
</html>]]>

Make sure to pick font followed by - and then size, 12px.