Zamień : 72 km na h = m/s 5 m/s = km/h

72km/h = 72*1000m/3600s =20m/s 5m/s = 5/1000 *3600 = 18km/h

72 km na h=72*1000m/3600=20m/s 5 m/s=5*1:1000km/1:3600=18km/h liczę na naj ;D