DEERFIELD BEACH, Fla. — Troubled rapper-singer XXXTentacion was shot and killed Monday in Florida in what police called an apparent robbery attempt.The 20-year-old rising star, whose real name is Jahseh Dwayne Onfroy, was pronounced dead Monday evening at a Fort Lauderdale-area hospital, the Broward Sheriff's Office said. He was shot earlier outside a Deerfield Beach motorcycle dealership.XXXTentacion had been at RIVA Motorsports checking out inventory, sheriff's public [...]