Question

express 84 km/h in metre/sec

Answer 1

1 hour = 60*60 = 3600 seconds
1 km = 1000 metres

= $\frac{84*1000}{3600*1}$                           {here 1 is hour}

= $\frac{70}{3}$
= 23.33 metre/sec

Answer 2

my answer for this question is 23.33 m/s