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.
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Question: Passage: Eisenhower did provide France with bombers and non-combat personnel. After a few months with no success by the French, he added other aircraft to drop napalm for clearing purposes. Further requests for assistance from the French were agreed to but only on conditions Eisenhower knew were impossible to meet – allied participation and congressional approval. When the French fortress of Dien Bien Phu fell to the Vietnamese Communists in May 1954, Eisenhower refused to intervene despite urgings from the Chairman of the Joint Chiefs, the Vice President and the head of NCS. Question: What did American bombers drop on Vietnam?

Answer: napalm


Question: Passage: Simultaneous videoconferencing among three or more remote points is possible by means of a Multipoint Control Unit (MCU). This is a bridge that interconnects calls from several sources (in a similar way to the audio conference call). All parties call the MCU, or the MCU can also call the parties which are going to participate, in sequence. There are MCU bridges for IP and ISDN-based videoconferencing. There are MCUs which are pure software, and others which are a combination of hardware and software. An MCU is characterised according to the number of simultaneous calls it can handle, its ability to conduct transposing of data rates and protocols, and features such as Continuous Presence, in which multiple parties can be seen on-screen at once. MCUs can be stand-alone hardware devices, or they can be embedded into dedicated videoconferencing units. Question: What feature enables an MCU to allow for multiple parties to be seen on screen at the same time?

Answer: Continuous Presence


Question: Passage: In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide. CDs are increasingly being replaced by other forms of digital storage and distribution, with the result that audio CD sales rates in the U.S. have dropped about 50% from their peak; however, they remain one of the primary distribution methods for the music industry. In 2014, revenues from digital music services matched those from physical format sales for the first time. Question: How many CDs had been distrubuted worldwide by 2007?

Answer:
200 billion