deletions | additions       diff --git a/Problem 2.tex b/Problem 2.tex  index e700088..b236cb3 100644  --- a/Problem 2.tex  +++ b/Problem 2.tex 
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\begin{equation}  \frac{A_V}{\rm{N_H}}=5.3\times10^{-22}~\rm{mag~cm^{2}}  \end{equation}  \noindent which is Draine's Eq.~21.7.