Input: Article: The battle of Iwo Jima ("Operation Detachment") in February 1945 was one of the bloodiest battles fought by the Americans in the Pacific War. Iwo Jima was an 8 sq mile (21 km2) island situated halfway between Tokyo and the Mariana Islands. Holland Smith, the commander of the invasion force, aimed to capture the island, and utilize its three airfields as bases to carry out air attacks against the Home Islands. Lt. General Tadamichi Kuribayashi, the commander of the island's defense, knew that he could not win the battle, but he hoped to make the Americans suffer far more than they could endure.

Now answer this question: How many airfields were on Iwo Jima?

Output: three

Input: Article: The service's B-2A aircraft entered service in the 1990s, its B-1B aircraft in the 1980s and its current B-52H aircraft in the early 1960s. The B-52 Stratofortress airframe design is over 60 years old and the B-52H aircraft currently in the active inventory were all built between 1960 and 1962. The B-52H is scheduled to remain in service for another 30 years, which would keep the airframe in service for nearly 90 years, an unprecedented length of service for any aircraft. The B-21 is projected to replace the B-52 and parts of the B-1B force by the mid-2020s.

Now answer this question: When did the B-2A aircraft enter into service of the US Air Force?

Output: 1990s

Input: Article: The culture of Greece has evolved over thousands of years, beginning in Mycenaean Greece and continuing most notably into Classical Greece, through the influence of the Roman Empire and its Greek Eastern continuation, the Eastern Roman or Byzantine Empire. Other cultures and nations, such as the Latin and Frankish states, the Ottoman Empire, the Venetian Republic, the Genoese Republic, and the British Empire have also left their influence on modern Greek culture, although historians credit the Greek War of Independence with revitalising Greece and giving birth to a single, cohesive entity of its multi-faceted culture.

Now answer this question: What do historians credit with revitalizing Greek culture?

Output:
Greek War of Independence