Which border-radius value is used to round the corners of this heading?

<html>
<head>
<style>h3 {text-align: center;border-radius: 30px 0 0 0;width:250px;background-color:lightGreen;}</style> </head><body>
  <h3>%Rounding up for dummies%</h3>
  <h4>A How-To Ebook</h4>
</body>
</html>]]>
The first valueThe third valueThe fourth valueThe second value

The first value.