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  \href{http://www.math.toronto.edu/~drorbn}{Dror Bar-Natan}: \href{http://www.math.toronto.edu/~drorbn/classes}{Classes}:
  \newline \href{http://www.math.toronto.edu/~drorbn/classes/\#2526}{2025-26}: \href{http://drorbn.net/26-1301}{MAT 1301 Algebraic Topology}:
}~{\LARGE\bf Homework Assignment 6}
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  \newline\null\hfill Due March 13 at 11:59pm
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Carefully read about the 5-lemma on page 129 of Hatcher's book (\url{https://pi.math.cornell.edu/~hatcher/AT/ATpage.html}), and then answer 
problems 24, 25, 26, 27, and 31 on page 133 of the same book.

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