https://www.reuters.com/article/us-facebook-cambridge-analytica/facebook-under-pressure-as-u-s-eu-urge-probes-of-data-practices-idUSKBN1GV1V6 >Facebook Inc Chief Executive Mark Zuckerberg faced calls on Monday from U.S. and European lawmakers to explain how a consultancy that worked on President Donald Trump's election campaign gained improper access to data on 50 million Facebook users.