deletions | additions       diff --git a/layout.md b/layout.md  index 34d5f4b..36ea06f 100644  --- a/layout.md  +++ b/layout.md 
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From_5_we_can_see__.tex  Inverse_is_also_true_if__.tex  Then_vec_v_t_Delta__.tex  From_3_vec_a_t__.tex