A practical problem states that a car travels 60 km/h and a truck travels 40 km/h. If they start at the same point and travel in the same direction, how far apart will they be after 2 hours?
Answer: A. 20 km
In 2 hours, the car travels 120 km and the truck travels 80 km. The difference is 120 km - 80 km = 40 km.