Nine flight attendants from six states said Monday they are suing the Centers for Disease Control and Prevention over the federal mask mandate on public transportation, arguing the COVID-19 rule obstructs their normal breathing over many hours and threatens aviation security because passengers refuse to comply. They want a judge to vacate the rule, which was recently extended to April 18, and prevent the CDC and the Department of Health and Human Services from issuing such a mandate again. The attendants filed suit in the U.S. District Court for the District of Colorado because one plaintiff, Victoria Vasenden of Southwest...