title: How to get last element/element at the specified index in the ObservableCollection
body: <p><strong>1.</strong> How to get last element in the <code>ObservableCollection</code>?</p>
  
  <p><strong>2.</strong> How to get element at the specified index in the <code>ObservableCollection</code>?</p>
  
  <p>In java it's just <strong>1.</strong><code>collection.get(collection.size()-1);</code>  <strong>2.</strong><code>collection.get(index);</code> How to get it in c#?</p>