Which of these is the law of 'Double Negation'?
neg(PlorQ)equivnegPlandnegQ\\neg(P \\lor Q) \\equiv \\neg P \\land \\neg Qneg(PlorQ)equivnegPlandnegQ
PlorPequivPP \\lor P \\equiv PPlorPequivP
negnegPequivP\\neg \\neg P \\equiv PnegnegPequivP
PlandnegPequivFalseP \\land \\neg P \\equiv FalsePlandnegPequivFalse