WASHINGTON, April 18, 2008 – When 20 recruits gathered yesterday at the Baltimore Military Entrance Processing Station to sign their enlistment contracts, none needed a pen. U.S. Army recruit Krista N. Hearne, 19, of Salisbury, Md., poses with the electronic Army enlistment contract she signed with her fingerprint as she became the first person to enlist in the U.S. military using biometric signatures. Photo by Army Lt. Col. Robert S. Larsen (Click photo for screen-resolution image);high-resolution image available. Instead, they read their contracts on a computer screen, then pressed their index fingers onto an electronic pad next to it,...