Normally you're supposed to be quiet at the library.Not so Sunday afternoon, March 31, when a group of singers from the Opera Company of North Carolina will make a return engagement in the meeting room of the Chapel Hill Public Library.Opera About Town, they're called, and they will present a free informal concert called "Favorite Italian Arias" at 3 p.m. The show is a Friends of the Chapel Hill Public Library Sunday Series presentation.Opera About Town played to a full house and rave reviews at the library in January. They're back for another show, and chances are the room will fill up in a hurry again. The program is a preview of the full concert scheduled for April 5 at Meymandi Concert Hall in the Progress Energy Center in Raleigh.The singers will perform selections from the Opera Company's upcoming spring concert, "Va Pensiero -- Favorite Italian Arias," which some of Italian opera's most exhilarating moments. Music will be chosen from operas including "The Barber of Seville," "Norma," "Elixer of Love," "Nabucco," "Rigoletto," "Aida," "Tosca," "Turnadot" and "La Traviata."For more than 10 years, the Opera Company of North Carolina has presented a host of full-scale opera productions.For more information call 919-792-3850 or see www.operanc.comOpera returns to the library