Use truth tables to determine whether the argument forms in 6- 11 are valid. Indicate which columns represent the premises and which represent the conclusion, and include a sentence explain- ing how the truth table supports your answer. Your explanation should show that you understand what it means for a form of argument to be valid or invalid. 6. 9 7. P P 9 q Vr 8. pvq 9. Pr r .. r рля пр PV ~q ~r