Which of these is logically equivalent to PiffQP \\iff QPiffQ?
neg(PlandQ)\\neg(P \\land Q)neg(PlandQ)
(PimpliesQ)land(QimpliesP)(P \\implies Q) \\land (Q \\implies P)(PimpliesQ)land(QimpliesP)
(PlorQ)land(negPlornegQ)(P \\lor Q) \\land (\\neg P \\lor \\neg Q)(PlorQ)land(negPlornegQ)
PimpliesQP \\implies QPimpliesQ