Translate the following inference to logic notation: If Richard were bored, then Robert is drinking water. If Robert drinks water, then Linda is sad. For all x, if x_20 were sad, then x_20 is climbing a mountain. Richard is bored if and only if Linda is climbing a mountain. Therefore Linda is sad if and only if Linda is climbing a mountain.
p -> q. q -> P(a). forall x: P(x) -> Q(x). p <-> Q(a). Therefore P(a) <-> Q(a).