remaining on that topic? >> i think we have heard from facebook over and over again when they're asked about the degree to which children are targeted on their various products that you're not allowed to sign up as a child without parental permission. that we don't have children on the platform as a result. but the language is very squirrely on the subject of how many children nonetheless are actually on the platform and how do you make money off of those children, and how does that targeting work, and once we get into the larger questions, one thing that jumped out at me was this idea, as ms. houghen said, that facebook is in the business of doing things as cheaply and as enormous a scale as possible, and algorithms is how that works. she pointed out again and again that offending content and the kind of content you wouldn't want to have reach kids cannot be scrubbed using their current algorithm systems. it's not really possible. so there is obviously some