Determine whether the following arguments are either valid or invalid by using the indirect method only of establishing validity. Circle your answer. Show all of your work for full credit. 1. 1. G⊃(I∨D)/(I⋅D)⊃B//∼G⊃B 2. (∼J∙∼K)/(L⊃J)/(M⊃K)/(M⊃∼L)⊃∼(N∙O)//∼N 3. ∼(O⋅Z)⊃(M∼A)/M⊃R/Z≡∼O/∼R∨A//∼O≡∼R (Z⋅K)v∼(R⊃O)/(O∨M)⊃∼R/(M⋅K)≡R//∼Z≡O (A⊃B)⊃(C⋅D)/(∼A∨∼B)⊃E/∼E∥(∼C⋅∼D)⊃∼E B⊃(E∙D)/(∼Ev∼F)/E⊃(B∨G)/G⊃(D⊃F)//Gv∼E