A bipartisan team of senators say they have serious questions about how the Pentagon and State Department track and monitor U.S. weapons sold around the globe, especially those used in the civil war in Yemen, and they are seeking answers from Defense Secretary Lloyd Austin. A letter to Austin , signed by Sens. Elizabeth Warren (D-MA), Mike Lee (R-Utah) and Bernie Sanders (I-VT), says they believe the United States is “failing to properly monitor whether U.S.-origin equipment is being used...