Two maglev trains, P P\,P and QQQ, run on parallel adjacent tracks. Train P P\,P is traveling due North at 240 km h-1, while train Q Q\,Q is traveling due South at 300 km h-1. Find the speed at which train Q Q\,Q is moving relative to a passenger sitting in train PPP, giving your answer in m s−1\text{m s}^{-1}m s−1.
16.7 m s−116.7\text{ m s}^{-1}16.7 m s−1
150 m s−1150\text{ m s}^{-1}150 m s−1
540 m s−1540\text{ m s}^{-1}540 m s−1
60 m s−160\text{ m s}^{-1}60 m s−1