Context: In Article 3 of the Treaty of San Francisco between the Allied Powers and Japan, which came into force in April 1952, the U.S. put the outlying islands of the Ryukyus, including the island of Okinawa—home to over 1 million Okinawans related to the Japanese—and the Bonin Islands, the Volcano Islands, and Iwo Jima into U.S. trusteeship. All these trusteeships were slowly returned to Japanese rule. Okinawa was returned on May 15, 1972, but the U.S. stations troops in the island's bases as a defense for Japan.

Question: When did Artcle 3 of the Treaty of San Francisco come into effect?
Answer: April 1952

Question: How many people lived on the island of Okinawa?
Answer: over 1 million

Question: When was Okinawa finally returned?
Answer: May 15, 1972

Question: Why did the US have troops on Okinawa?
Answer: as a defense for Japan.

Question: When did Article 2 of the Treaty of San Francisco come into effect?
Answer: Unanswerable

Question: How many people lived on the island of Bonin?
Answer: Unanswerable

Question: When was San Francisco finally returned?
Answer: Unanswerable

Question: Why did the Japanese have troops on Okinawa?
Answer: Unanswerable

Question: Who put the outlying islands of the Ryukyus into Bonin trusteeship?
Answer: Unanswerable