Heroic acts); 4A. " I'M ALL ears!"; IN AWE (27D. Blown away);    Bob Marley’s “ I SHOT the Sheriff” ; LEWIS (7D. Explorer with Sacagawea ); MECCA (61A. Pilgrimage destination); MOBIL (26D. 1999 Exxon merger partner); NIVEA (15A. Big name in skin care); RABAT (57A. North African capital); ROSEN (32D.