Translate the following inference to logic notation: For all x, if x_8 were a sailor, then x_8 is sad. For all x, if x_8 were sad, then x_8 is a sailor. Jennifer is sad or James is writing a letter. If James writes a letter, then Jennifer is a sailor. Therefore Jennifer is a sailor.
forall x: P(x) -> Q(x). forall x: Q(x) -> P(x). Q(a) or p. p -> P(a). Therefore P(a).