https://qz.com/1251646/what-we-learned-from-mark-zuckerbergs-congressional-testimony/ >After a long week, Facebook CEO Mark Zuckerberg is done with the first round of his face-off with Congress. >He heard some challenging questions, and some admonitions, but overall, the Washington tour went well for the 33-year-old executive. With no major stumbles, the stock market—currently the most important check on his company’s power—responded favorably to his performance.