Boeing and at least one other U.S. heavy-equipment manufacturer resumed production and some states rolled out aggressive reopening plans Monday, despite nationwide concerns there is not enough testing yet to keep the coronavirus from rebounding. Boeing said it was putting about 27,000 people back to work this week building passenger jets at its Seattle-area plants, with virus-slowing precautions in place, including face masks and staggered shifts. Doosan Bobcat, a farm equipment maker and North Dakota’s largest manufacturer, announced the return of about 2,200 workers at three factories around the state.