Turing-decidable languages problem:

If this is difficult to read, it is asking to show that Turing-decidable languages are closed under union, intersection, complement, and set difference. I had thought, at least for intersection, that this would make them Turing-recognizable, so I am stuck. Thank you for your time. Probleni Show that the Turing-decidable languages are chesed ude ) taio b) intersectin