Northrop Grumman CEO Speaking At The Morgan Stanley Laguna Conference Says U.S. Air Force To Conclude B-21 Fleet-Size Review By Year-End; "We Are Far Along In Discussions With Lockheed Martin As To Be The Solid Rocket Motor Provider For A Portion Of Their Buy"; Says Co In Active Discussions Covering 10 Agreements Across Eight Weapons Programs; Co Planning First Sentinel Missile Test In 2027, Which Is Earlier Than Was Anticipated