Mark Zuckerberg urges people to wear a mask to help 'keep this country open' (FB)

· Mark Zuckerberg is calling on people to wear masks to help halt the spread of the coronavirus. 
· "Covid is spreading quickly again and masks help keep people healthy and keep the country open," Zuckerberg wrote in an Instagram caption accompanying a photo of him and his wife, Priscilla Chan, wearing masks.
· While...