title: Merge method in Hartl's Tutorial
body: <p>Just a simple question, I'm assuming it has a simple answer from Hartl's Chapter 4.6 Exercise #4. Not sure what the value should be? 
  Is it <code>true</code> or <code>false</code>? Thank for any clarification.</p>
  
  <p>Find an online version of the Ruby API and read about the Hash method merge. What is the value of the following expression?</p>
  
  <pre><code>  { "a" =&gt; 100, "b" =&gt; 200 }.merge({ "b" =&gt; 300 })
  </code></pre>