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    Question: Who invented flexible photographic film?
    Answer: In the late 1800s the U.S. inventor George Eastman invented flexible film and a small, easy-to-use camera. These made it possible for anyone to take photographs.
    Question: When did the compact disc first appear on the market?
    Answer: Compact discs that stored sound were introduced in 1982. By the mid-1980s new discs called CD-ROMs could store pictures and computer programs.
    Question: When was the DVD introduced?
    Answer: The DVD, which means "digital video disc" or "digital versatile disc," appeared in 1995. DVDs are often used to store movies.
    Question: Who is the maker of the iPhone?
    Answer: Apple Computer is the maker of the iPhone. The telephone and miniature computer first went on sale in 2007.
    Question: To which of these devices is the cellular telephone most closely related?
    Answer: The cellular telephone carries voice, text, and other digital signals via radio waves, like a two-way police radio.
    Question: Which of these is a file format for digital images?
    Answer: With JPEG, a digital image can be compressed to 5 percent of its original size, making it easy to transfer electronically and store.
    Question: What does fiber optic cable resemble, in terms of size?
    Answer: A fiber optic cable is about as big around as a human hair but can carry more information than a much larger electrical wire.
    Question: Which of these is not a telephone?
    Answer: An iPod is a music-listening device. It lacks a phone. Its cousin, the iPhone, has a telephone built in.
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