Answer:
1. What made Rafferty believe that the visitors at Mr. Alsop's place were
Aliens?
The reason why he thought that the visitors were not normal and were Aliens is when he was just staring at them from the corner of his eyes. He didn't wanna be caught because he realized that they were no ordinary people.
2. When did Rafferty realise he had a story? Who did he think had built the spaceship?
He realized that he had a story when he saw the spaceship. He first initially thought it was a plane. But soon he realized that it was something without wings unlike a place. That's when he realized it was a spaceship and he had a story.
3. Who did he think had built the spaceship?
He thought that the Aliens had built the spaceship. It could also be from the metal makers since it was found from their work place