You can ask one yes/no question to one guard (maybe liar, maybe truth-teller) to choose the safe door out of two; which classic question forces a truthful indication?

"If I asked you whether this door leads to freedom, would you say 'yes'?"

"Does this door lead to freedom?"

"Would the other guard say this door leads to freedom?"

You may ask one yes/no question to one of two islanders; one always lies and one always tells the truth. To find which road leads to the village, which question should you ask a guard about a given road?

"If I asked the other guard whether this road leads to the village, would he say yes?"

"Does this road lead to the village?"

Either (A knight & B knave OR A knave & B knight)

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01You can ask one yes/no question to one guard (maybe liar, maybe truth-teller) to choose the safe door out of two; which classic question forces a truthful indication?
02A says, "We are both knaves." What are A and B?
03A says, "At least one of us is a knave." B says nothing. What are A and B?
04You may ask one yes/no question to one of two islanders; one always lies and one always tells the truth. To find which road leads to the village, which question should you ask a guard about a given road?
05A says, "I am a knight." What can you conclude about A?
06Three islanders: A says "B and C are opposite types." B says "A and C are opposite types." C says "A and B are opposite types." Which assignment fits?
07A says, "B is a knight." B says, "A and I are the same." Who are they?
08An islander says, "I am a knave." What can you conclude?
09A says, "B is a knave." B says, "C is a knave." C says, "A is a knave." What is the consistent assignment?
10A says, "B is a knave." B says, "A is a knave." Who is which?