... discovered to be false (by negating), the argument would fall apart ... .
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> When negating the truth of an answer ... choice, if negating causes the argument to be ...
... cannot conclude /subsidized ------- /outside control (negating the sufficient means the rule ... ). We cannot conclude anything from negating the sufficient condition "subsidized" so ...
... don't want the existential quantifier to come after a universal ... . An example of an existential quantifier preceding a universal is Valid ... C. Some is the existential quantifier that precedes the universal B ...
Doesn't matter all that much as long as you're aware of the symbols. Make sure to be consistent because wrongfully negating is fatal. I prefer SE for the same reasons highlighted above: it's much more clear.