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<sec id="sec45">
 <title>The Answers</title>
 <p>Students should use the answers below to check
  their understanding.</p>
 <answer-set>

  <answer pointer-to-question="q1">
   <p>B</p>
  </answer>

  <answer pointer-to-question="q2" id="ans2">
   <p>false</p>
   <explanation pointer-to-explained="ans2">
    <p>Soviet cosmonaut Georgy Beregovoy was born three months
     and three days earlier than United States astronaut John 
     Glenn, whose birth date is July 18, 1921.</p>
   </explanation>
  </answer>

  <answer pointer-to-question="q3">
   <answer-set>
    <answer pointer-to-question="q3a" id="ans3a">
     <p>1</p>
    </answer>

    <answer pointer-to-question="q3b" id="ans3b">
     <p>3</p>
    </answer>

    <answer pointer-to-question="q3c" id="ans3c">
     <p>2</p>
    </answer>

    <explanation pointer-to-explained="ans3a ans3b ans3c">
     <p>Glenn resigned from NASA on January 16, 1964. He 
      won election to the United States Senate in 1974. On 
      October 29, 1998, he became the oldest person to fly 
      in space.</p>
    </explanation>
   </answer-set>
  </answer>

  <answer pointer-to-question="q4">
   <p>This selection is a biographical sketch of John Glenn's 
    career.  The sketch focuses upon his achievements at NASA, 
    notably his becoming the first American to orbit the Earth 
    in 1962.  The biography also discusses his retirement from 
    the Marine Corps and subsequent election to the United 
    States Senate, where he continued his interest in space 
    flight.  The bio concludes with his participating at age 77 
    in a Space Shuttle mission.</p>
  </answer>

 </answer-set>
</sec>
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