science, belief in technology. so the republican party is not exactly attractive to silicon valley. that said, they may disagree with some of the regulatory approach. but it's long past time that we need to regulate them. >> i would say most republicans i talk to do believe in universities. but i take your point. jo ling kent, what's at stake for mark zuckerberg this week? >> this is the first time mark zuckerberg has had a test of this size before. so what we're expecting to see is how it impacts advertisers. how it impacts how much time you and i are spending as average users out there. because we're already seeing that the amount of time spent on facebook decline as they make these changes. now congress is probably going to make some demands in addition to asking questions. expect this to have a serious impact on the company. and trust. that's the other big one. >> sarah fisher, what does your reporting say? is facebook only making these moves because they're seeing a real economic impact, or it is because they actually believe in what they're doing now? >> i think it's little bit of both. look, you're completely right.