deletions | additions       diff --git a/layout.md b/layout.md  index 1f416a4..a660ca1 100644  --- a/layout.md  +++ b/layout.md 
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Intro1.tex  figures/Drake4/Drake1.jpg  Intro.tex  How common are planets?.tex ?.tex  Equation.tex  figures/Drake3/Drake_explained.png  Parameters.tex