Mr Wincklebotham is travelling on the train from Enviroland to Visionworld, with his baby Sylvana.
Sylvana is very afraid of the dark and starts to scream if she is in the dark for more than 90 seconds.
The train has to travel through a very dark tunnel which is 1 km long. If the train is 1 km long and is travelling at 60 km/h, how long does it take to go through the tunnel? Will Sylvana start to scream?