<course>
  <chapter url_name="GradedChapter">
    
    <vertical url_name="Homework1">
      <problem url_name="H1P1">
        <optionresponse>
          <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
          <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
        </optionresponse>
      </problem>
      
      <abtest experiment="HiddenProblem">
        <group name="SeeProblem" portion="1">
          
          <problem url_name="H1P2">
            <optionresponse>
              <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
              <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
            </optionresponse>
          </problem>
          
        </group>
        
        <group name="HiddenProblem" portion="0">
          
          <problem url_name="H1P3">
            <optionresponse>
              <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
              <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
            </optionresponse>
          </problem>
          
        </group>

      </abtest>
    </vertical>
    
    
    <videosequence url_name="Homework2">
      <vertical url_name="Homework2Inner">
        
        <problem url_name="H2P1">
          <optionresponse>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
          </optionresponse>
        </problem>

        <problem url_name="H2P2">
          <optionresponse>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
          </optionresponse>
        </problem>

      </vertical>
    </videosequence>
    
    <videosequence url_name="Homework3">
      <vertical url_name="Homework3Inner">
        
        <problem url_name="H3P1">
          <optionresponse>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
          </optionresponse>
        </problem>

        <problem url_name="H3P2">
          <optionresponse>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
            <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
          </optionresponse>
        </problem>
        
      </vertical>
    </videosequence>
    
    <problem url_name="FinalQuestion">
      <optionresponse>
        <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
        <optioninput options="('Correct', 'Incorrect')" correct="Correct"></optioninput>
      </optionresponse>
    </problem>
    
  </chapter>
</course>
