An artist on a beach used one of these objects while a plane flew above in the piece 747. Xiao Lu used one of these objects at the premiere of her 1989 installation Dialogue. A fight broke out over one of these objects (-5[1])during Marina Abramović’s piece Rhythm (10[1])0. The Mozambican artist Kester used these objects to make both the sculpture Tree of Life and a throne. Three years before being crucified onto a Volkswagen Beetle in the piece (10[1])Trans-Fixed, Chris Burden had a friend use one of these objects on him in his most famous work of performance art. In the most famous photograph by Eddie Adams, a man nonchalantly uses one of these objects on another man in Saigon. For 10 points, in a 1968 incident at The Factory, what sort of object did Valerie Solanas use on Andy Warhol? ■END■ (10[1])