function [] = testCircleArea()
     tolerance = 0.01;

     if (___________________________________________________)
     disp('error calculating circleArea(3)');

     elseif (__________________________________________________)
     disp('error calculating circleArea(4)');

     elseif (__________________________________________________)
     disp('error calculating circleArea(4)');
     else
     disp('All tests executed successfully.');
  end         
