Answer:
The sprinter
Explanation:
Change cyclist to same units as sprinter (m/s)
20 km = 20x1000 m = 20000 m
1 hour = 60 minutes = 60 x 60 = 3600 sec
So 20 km/hr = 20,000 m / 3600 sec = 5.6 m/s
The sprinter is faster as he travels at 8 m/s.
(Similarly if you change the sprinter's speed into km/hr
you should get 28.8 km/hr)