Of all airline flight requests received by a certain ticket broker, 70% are domestic travel (D) and 30% are for international flights (I). Define X to the number that are for domestic flight among the next three requests receieved. Assuming independence of successive requests, determine the probability distrubution of x. (Hint: One possible outcome is DID, with the probability (0.7)(0.3)(0.7)=0.147.)