Hi Harry,
Yes, a Semi-Rigid Dryer vent with clamps will work with this Samsung dryer; however, it is recommended to use rigid exhausts. A 3-prong dryer cord will work with this dryer model plugged into a 30 Ampere receptacle.
No, the y-connector and the short water hose are not supplied with this model, only with DVE50R5400 or DVG50R5400 models. The y-connector and short water hose are not required but are recommended to be used when supplied.
Leo