deletions | additions       diff --git a/The_Virgo_cluster_is_so__.tex b/The_Virgo_cluster_is_so__.tex  index 234da3a..4c58b36 100644  --- a/The_Virgo_cluster_is_so__.tex  +++ b/The_Virgo_cluster_is_so__.tex 
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What distance do you get? Current best estimates lie in the range 35 --- 80  Mpc, but don't worry if your answer is outside this, it is a very difficult  measurement (I got 30 Mpc when I tried it). measurement.  Each student in the group should do their own measurements and you should compare the   results of each group member.  How might you go about improving your estimate?  By far the worst feature of this calculation is the assumption that these