Answer:
28 km/h
Explanation:
so i multiplies 4 times 35 since it took 4 hours to return and they were going 35 km/h and got 140 so the town is 140 kilometers away
then i divided 140 by 5 since it took 5 hours to go over there and its 140 km away and got 28
so if they took 5 hours to drive 140 kilometers to go they would average 28 km/h going to the town