This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
--------
Question: Passage: The Space Age is a period encompassing the activities related to the Space Race, space exploration, space technology, and the cultural developments influenced by these events. The Space Age began with the development of several technologies that culminated with the launch of Sputnik 1 by the Soviet Union. This was the world's first artificial satellite, orbiting the Earth in 98.1 minutes and weighing in at 83 kg. The launch of Sputnik 1 ushered a new era of political, scientific and technological achievements that became known as the Space Age. The Space Age was characterized by rapid development of new technology in a close race mostly between the United States and the Soviet Union. The Space Age brought the first human spaceflight during the Vostok programme and reached its peak with the Apollo program which captured the imagination of much of the world's population. The landing of Apollo 11 was an event watched by over 500 million people around the world and is widely recognized as one of the defining moments of the 20th century. Since then and with the end of the space race due to the dissolution of the Soviet Union, public attention has largely moved to other areas. Question: What did Sputnik 1 usher in?

Answer: The Space Age

Question: Passage: On 30 September, Zhou Enlai warned the United States that China was prepared to intervene in Korea if the United States crossed the 38th parallel. Zhou attempted to advise North Korean commanders on how to conduct a general withdrawal by using the same tactics which had allowed Chinese communist forces to successfully escape Chiang Kai-shek's Encirclement Campaigns in the 1930s, but by some accounts North Korean commanders did not utilize these tactics effectively. Historian Bruce Cumings argues, however, the KPA's rapid withdrawal was strategic, with troops melting into the mountains from where they could launch guerrilla raids on the UN forces spread out on the coasts. Question: Who vowed to intervene if the US was to engage in conflict North of the 38th parallel?

Answer: China

Question: Passage: The most common forms of uranium oxide are triuranium octoxide (U
3O
8) and UO
2. Both oxide forms are solids that have low solubility in water and are relatively stable over a wide range of environmental conditions. Triuranium octoxide is (depending on conditions) the most stable compound of uranium and is the form most commonly found in nature. Uranium dioxide is the form in which uranium is most commonly used as a nuclear reactor fuel. At ambient temperatures, UO
2 will gradually convert to U
3O
8. Because of their stability, uranium oxides are generally considered the preferred chemical form for storage or disposal. Question: Along with UO2, what is the commonest form of uranium oxide?

Answer:
triuranium octoxide