Question

b)How did Charlie understand that Sam had found the Third Level?​

Answer 1

Answer:

Ans.: The way Charley came across Sam's letter was surrounded in mystery. Among his oldest first-day covers, he found an envelope. The envelope containing the letter bore the address of his grandfather. ... In the letter Sam had informed Charley that he was living on the third level.

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Answer 2

Answer:

Sam had written that he had found the Third Level. It means that Charley was correct about the Third Level. Further he had been putting up at Galesburg, Illinois for two weeks where people had been enjoying a romantic life. He asked Charley and Louisa to go there.