https://www.reuters.com/article/us-health-coronavirus-amazon-com-senator/u-s-senators-question-amazon-on-coronavirus-safety-at-warehouses-idUSKBN2173IZ >Four Democratic U.S. senators on Friday expressed concern in a letter to Amazon.com Inc Chief Executive Jeff Bezos that the world's largest online retailer has not given enough support to warehouse staff during the coronavirus outbreak, according to a copy of the message seen by Reuters.