Suppose that all you know about some argument (in PL) are the following facts: it has two premisses and a conclusion the first premise is a tautology the second premise is a contradiction For each of the following claims, say whether it is (a) true, (b) false, or (c) you don't have enough information to know whether it is true or false and justify your answers: (i) The argument is valid. (ii) The argument is sound. 2. What is the main connective of the following wff? A (Note: the wff has three occurrences of the negation connective in it. So it is not enough to answer 'negation'. You must indicate by circling, underlying, highlighting, or drawing an arrow pointing to it exactly which occurrence is the main connective.) Justify your answer. (Note: your justification should include and refer to a construction of the wff A in which you indicate again by circling, underlying, highlighting, or drawing an arrow pointing to it exactly which connective is added at each step. That is, do not simply say that negation or is added: indicate exactly which occurrence is added at each step.)