Translate the following inference to logic notation: For all x, x_18 will not work. For all x, x_18 will read a book if and only if x_18 will listen to a song. Charles is an office clerk or Susan is a server. For all x, x_18 will read a book if and only if x_18 will work. Charles is an office clerk if and only if David is listening to a song. Therefore Susan is a server.
forall x: ~P(x). forall x: Q(x) <-> R(x). p or q. forall x: Q(x) <-> P(x). p <-> R(a). Therefore q.