title: Writing a regex expression
body: <p>How do I write a regex expression starting with A and the second through fourth characters in the string must be digits and the fifth character must be a lowercase letter? </p>
  
  <pre><code>/[A | B | C]{2-4}[a-z]/
  </code></pre>
  
  <p>Sorry I am just not getting it, but that's my go at it</p>