The speed v is 12 m/s.
You need to convert the seconds to hours and meters to kilometers:
3600s = 1 hr
If you divide 3600 on both sides you will get
1 s = (1/3600) hr
1000m = 1 km
If you divide 1000 on both sides you will also get
1 m = (1/1000) km
v = [(12/1000) km] / [(1/3600) hr]
v = [(12*3600)/1000] km/hr
v = 216/5 km/hr
The distance in 4 hours is
d = [(216/5) km/hr] * 4hr
d = 864.50 km
This is why your answer should be 12 m/s
Hope this helps!! - Queenb369
