Callstack:
    at Inorganic_Chemistry/Descriptive_Chemistry/Main_Group_Elements/Group_18:_The_Noble_Gases

MindTouch.Deki.Script.Runtime.DekiScriptUndefinedNameException: reference to undefined name 'media' Exception of type 'MindTouch.Deki.Script.Runtime.DekiScriptUndefinedNameException' was thrown.
  at MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluation.Visit (MindTouch.Deki.Script.Expr.DekiScriptVar expr, DekiScriptExpressionEvaluationState state) [0x00000] 
  at MindTouch.Deki.Script.Expr.DekiScriptVar.VisitWith[DekiScriptExpressionEvaluationState,Range] (IDekiScriptExpressionVisitor`2 visitor, DekiScriptExpressionEvaluationState state) [0x00000] 
  at (wrapper static-rgctx-invoke) MindTouch.Deki.Script.Expr.DekiScriptVar:static_rgctx_invoke_DekiScriptOutputBuffer/Range__this___IDekiScriptExpressionVisitor`2<DekiScriptExpressionEvaluationState, DekiScriptOutputBuffer/Range>_DekiScriptExpressionEvaluationState (MindTouch.Deki.Script.Expr.IDekiScriptExpressionVisitor`2<MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluationState, MindTouch.Deki.Script.Runtime.DekiScriptOutputBuffer/Range>,MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluationState)
  at MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluation.Visit (MindTouch.Deki.Script.Expr.DekiScriptCall expr, DekiScriptExpressionEvaluationState state) [0x00000] 
  at MindTouch.Deki.Script.Expr.DekiScriptCall.VisitWith[DekiScriptExpressionEvaluationState,Range] (IDekiScriptExpressionVisitor`2 visitor, DekiScriptExpressionEvaluationState state) [0x00000] 
  at (wrapper static-rgctx-invoke) MindTouch.Deki.Script.Expr.DekiScriptCall:static_rgctx_invoke_DekiScriptOutputBuffer/Range__this___IDekiScriptExpressionVisitor`2<DekiScriptExpressionEvaluationState, DekiScriptOutputBuffer/Range>_DekiScriptExpressionEvaluationState (MindTouch.Deki.Script.Expr.IDekiScriptExpressionVisitor`2<MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluationState, MindTouch.Deki.Script.Runtime.DekiScriptOutputBuffer/Range>,MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluationState)
  at MindTouch.Deki.Script.Compiler.DekiScriptExpressionEvaluation.Visit (MindTouch.Deki.Script.Expr.DekiScriptTryCatchFinally expr, DekiScriptExpressionEvaluationState state) [0x00000]