2023-2 Modal Logic (Segment 1) ① Determine whether the following valid in the systems indicated by the semantic tableau L(Lp ⊃ Lq) ∨ L(Lq ⊃ Lp) ML(p ⊃ LMp) ② Determine which of the following are valid in K, D, T, S4, S5, B by tableaux. L(p ∨ Lq) .⊃. Lq ∨ Lp M(p⊃p) Mp ⊃ LMMp Lp ∧ M(q ⊃ r) :⊃: L(p⊃q) ⊃ M(p ∧ r)