deletions | additions       diff --git a/The Moon.tex b/The Moon.tex  index 8218897..61ade72 100644  --- a/The Moon.tex  +++ b/The Moon.tex 
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\begin{align}  \frac{G M_\oplus}{a_m^2} &= \frac{4\pi^2 a_m^2}{P_m^2 a_m} \\  P_m^2 &= \frac{4\pi^2 a_m^3}{G M_\oplus} \\  a_m &= \left( \frac{G M_\oplus P_m^2}{4\pi^2} \right)^{1/3}\\   &= \left( \frac{6.7\times 10^{-8} \times 6\times 10^{27} \times (2.4\times10^6)^2}{4\times 9}  \end{align}  \item {\it What is the Moon's radius?}