Translate the following inference to logic notation: For all x, x_11 is not a mechanic. For all x, x_11 is a soldier or x_11 is a nurse. For all x, x_11 is a police officer. For all x, x_11 is a soldier if and only if x_11 is a mechanic. Therefore Mary is a nurse.
forall x: ~P(x). forall x: Q(x) or R(x). forall x: S(x). forall x: Q(x) <-> P(x). Therefore R(a).