sources" brian stelter, today big for facebook and they are saying yep, 126 million people could have seen these ads. they're trying to give it context and they're saying that is equivalent to 0.004% of the content in the news feed. how much does this number matter? >> yeah. 126 million is the exposure number, meaning when you're on facebook and you're just scrolling through your news feed you may have seen the sensational, bogus, sometimes made up stories coming from russian troll farms. some were ads and we've heard about the ads russia was buying to target various states before election day. we will see those ads this week thanks to the capitol hill hearings the important piece the truly fake news. not president trump's definition of fake news but made up stories designed to make you dislike hillary clinton. that's what was spreading thanks to these russian troll farms, stories that were divisive, meant to sow discord in the u.s. and a lot with anti-hillary