Translate the following inference to logic notation: If Robert listens to a song, then Jennifer is climbing a mountain. Robert is a musician if and only if Susan is sleeping. If Susan sleeps, then Jennifer is not climbing a mountain. Robert is listening to a song or Barbara is a mechanic. Barbara is a mechanic if and only if Jennifer is climbing a mountain. Therefore Robert is not a musician.
p -> q. r <-> s. s -> ~q. p or t. t <-> q. Therefore ~r.