PITTSBURGH (AP) — The sex assault case against Bill Cosby turns on serious questions about his actions with women behind closed doors, but the comedian and others unexpectedly fell into laughter Wednesday during questioning of one potential juror. At that point, he volunteered that his 21-year-old grandson already had sprung for the two of them to go to Las Vegas next month — which would conflict with the trial date. Cosby, once known as America's Dad for his role in his long-running sitcom, is charged with drugging and molesting a woman at his home near Philadelphia in 2004.