SOLUTION: 1. ~ A v ~ S Basic Assumption 2. ~ ~ S Basic Assumption 3. (A => ~ O) & (~ O => A) Basic Assumption 4. (~ O => ~ S) v A Basic Assumption / A => ~ S

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Eval error:

ModPerl::Util::exit: (120000) exit was called at /home/ichudov/project_locations/algebra.com/templates/Algebra/Questions/MoreLikeThis.pm line 159