For each of the following symbolized arguments, use a short-form truth table to test for validity. If the argument is valid, give a proof of its validity using the 18 rules of implication and replacement. If the argument is invalid, give a set of truth values for the variables such that the premises are true, but the conclusion is false.
9. i. (S • K) ➡️ R
ii. K
c. S ➡️ R