It was a busy week for Billy Mulholland, a freshman at the University of Massachusetts at Amherst. On Sunday, he scored free food at a welcome barbecue. Monday he went to a pep rally and saw comedian Lewis Black. Tuesday was the ”beach party” by the campus pond; Wednesday featured a speech by the hip-hop mogul Russell Simmons. Thursday night the local mall stayed open late just for Amherst students, and he was busy shopping until 2 a.m.