If Superman is able and willing to prevent evil, he would do so. If Superman is unable to prevent evil, he would be ineffective. If he is unwilling to prevent evil, he would be malevolent. If Superman exists, he is neither ineffective nor malevolent. Superman does not prevent evil. Argue that Superman does not exist. Let p = " Superman is able to prevent evil." q = " Superman is willing to prevent evil." r = "Superman prevents evil." s = "Superman is ineffective." t = "Superman is malevolent." u = "Superman exists." Write each premise in terms of p, q, r, w, t, u and logical operators