Question

How did the leader guess that somebody know about the secret cave​

Answer 1

Ali Baba found the treasure of the loot by the robbers in the cave. He filled his pockets and the bag with gold, ornaments and jewels

Much alarmed, he went softly down into the yard, and going to the first jar, while asking the robber, whom he thought alive, if he was in readiness, smelt the hot boiled oil, which sent forth a steam out of the jar. Hence he knew that his plot to murder Ali Baba and plunder his house was discovered

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