Impeachment on NPR

You might already be tired of hearing about impeachment, but in case you are not, here are some stories, short and long, that might help you understand what is going on in Washington. A short presentation can be found here (Your Senate Impeachment Trial Questions) 4 min 15 sec; a long presentation of the history of impeachments can be found here (Presidential Historians On What They're Watching For During The Senate Impeachment Trial) 46 min.
Nina Totenberg describes the role of the Chief Justice in an impeachment trial here. 6 min, 25 sec.
NPR's complete coverage of the impeachment can be found here.