[Sabhya Bhardwaj]

distance = 500km

time taken = 10hrs

speed = distance/time

= 500/10

=50 km/h

To convert quantities from km/h to m/s, multiply the said quantity by 5/18{simplified form of 1000/3600}

According to question : 50 x 5/18

= 250/18 m/s

= 13.8 m/s