NEW YORK (AP) – She rode her status as a Grammy-winning pop singer into Hollywood stardom by starring in “Grease.” And she waged a brave, decades-long, battle against breast cancer. So no matter what part of the entertainment world you’re into, there’s mourning for the loss of Olivia Newton-John, who died yesterday at age 73. From 1973-to-83, Newton-John was one of the world’s top popular entertainers, logging 14 top 10 singles in the U.S. She also starred with John Travolta in “Grease” and with Gene Kelly in “Xanadu.”