Question 1007494
Since distance = rate * time, or d = rt, then 
t = d/r = 171 km / 12.5 m/s = 171000 m / 12.5 m/s = 13680 seconds
This is 13680 / 60 = 228 minutes or 3 hours, 48 minutes.
Add that to 4:30 pm and get
8:18 pm