In Exercises 1527, either prove that the wff is a valid argument or give an interpretation in which it is false. (x)[P(x)Q(x)](y)[Q(y)R(y)](x)P(x)(x)R(x) In Exercises 1527, either prove that the wff is a valid argument or give an interpretation in which it is false. (x)[P(x)Q(x)](y)[Q(y)R(y)](x)P(x)(x)R(x)