Answer:
The speed is:
5 meters per second
In then seconds: 50 meters
Step-by-step explanation:
1 hour = 3600 seconds
1 km = 1000 meters
18km = 18*1000 = 18000 meters
then:
18km/h = 18000m/3600sec = 5m/s
The speed is:
5 meters per second
proportions:
5 meters ⇔ 1 second
W meters ⇔ 10 seconds
W = 5*10/1
W = 50 meters