Determine which of the following statements are conjunctions in propositional logic with a dot (•) as the main operator. check all that apply.
(~n ⊃ ~j) • ~(~r ⊃ ~e)
(b • ~l) ⋁ ~(f • ~u)
~a • ~~e
{[(m ⊃ (~d ⋁ s)] • [~~i ⋁ (l ⊃ c)]} ≡ {[z • ~(u ⋁ h)] • [(a ⋁ r) ⊃ ~d]}
(q ⊃ v) • j
[~m • ~(m ⋁ z)] ⊃ ~[(~b • ~c) • ~g]
~{~[~(a ⋁ m) ⊃ ~e] ≡ ~(v ⊃ n)} • g
~{[~~(a • ~m) ⊃ ~~x] • ~[~(w ≡ i) ≡ ~(b ≡ g)]}
(b • l) ≡ ~(~m ⋁ ~q)
~[(d ≡ ~w) ⋁ ~(~v ⊃ j)] • [~u ⋁ (~e • ~p)]