We can use the distance, rate, and time formulas.
We know that
r = d/t
Hence,
d = r * t
We have both the rate, and the time.
284.5 * 0.8 = 227.6
Therefore, the cities are 227.6 km apart.
For the sake of your learning, here is a YouTube video from which you can learn to convert km/h --> m/s
https://www.youtube.com/watch?v=AMGRQR_ANCU
With thanks,