A passenger sitting in a train A moving at \( 90 \, \text{km/h} \) observes another train B moving in the opposite direction for \( 8 \, \text{s} \). If the velocity of the train B is \( 54 \, \text{km/h} \), then length of train B is:
\( 320 \, \text{m} \)
\( 120 \, \text{m} \)
\( 200 \, \text{m} \)
\( 80 \, \text{m} \)
