Danka was watching a train with length l₁=120m, which was passing her with velocity v₁=60km·h⁻¹. She also saw a train of unknown length l₂ approaching from the opposite direction with velocity v₂=80km·h⁻¹. In order to find l₂, Danka measured the time the trains spent passing each other, i.e. the interval between the times when the fronts of the trains met and when the backs of the trains met. She measured t=9s. How long was the second train?