who r the slow learners here?

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    When NASA first started sending up astronauts, they quickly discovered
    that ball-point pens would not work in zero gravity. To combat this
    problem, NASA scientists spent a decade and $12 billion developing a pen
    that writes in zero gravity, upside down, on almost any surface
    including glass and at temperatures ranging from below freezing to over
    300 C.
    The Russians used a pencil.
 
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