title: How to print all keys from an object each on a separate line
body: <p>I can not figure out how to print each key on a separated line. </p>
  
  <p>The function prints each key of the input on a separate line. That is, it prints all keys of the key-value store separated by new line characters.</p>
  
  <p>I'm able to print all the keys, just not on separate lines like it asks.</p>
  
  <pre><code>function print_keys(x){
  console.log(Object.keys(x));
  }
  </code></pre>
  
  <p>Expected 
  "stand
  rip
  rating
  pollution
  fixed
  "
  But got "stand,rip,rating,pollution,fixed"</p>