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To solve this problem, you can use a process of elimination and logical reasoning. Here is one possible solution:
Ask the True oracle if the Random oracle is Random. If the True oracle says "DA", then you know that "DA" means "yes" and "BAL" means "no". If the True oracle says "BAL", then you know that "BAL" means "yes" and "DA" means "no".
Ask the False oracle if the Random oracle is Random. If the False oracle says "DA", then you know that "BAL" means "yes" and "DA" means "no". If the False oracle says "BAL", then you know that "DA" means "yes" and "BAL" means "no".
Now that you know the meaning of "DA" and "BAL", you can ask the Random oracle if he is Random. If he says "DA", then you know that he is the Random oracle. If he says "BAL", then you know that he is the False oracle.
Now that you know who the Random oracle is, you can ask him a question to which you know the answer and see whether he answers truthfully or not. If he answers truthfully, then the True oracle is the one who said the Random oracle was Random. If he answers falsely, then the False oracle is the one who said the Random oracle was Random.
You now know the identity of all three oracles.
Keep in mind this is one way of solving the problem, and there may be other ways to approach it as well.