NEED HELP WITH ALL PLEASE!!!

1) [15 marks total] Consider the proposition ((x(yz))(xy)(xz) a. [5 marks] Is it a tautology or a contradiction? b. [10 marks] Prove your answer for item a. without using a truth table. 2) [15 marks total] Consider the English sentence "I either go to school or I do not." a. [5 marks] Is it a tautology or a contradiction? b. [10 marks] Prove your answer for item a. without using a truth table. 3) [10 marks total] For each of the following propositions provide its truth table and derive an equivalent proposition in Disjunctive Normal Form (DNF). a. [5 marks] (pq)r b. [5 marks ](pq)(pr)