Answer: 58.8235 km/h
speed = distance/time
the distance is 10 km
the time is 10 minutes
the unit is not correct, so we first change minute to hour
so 10/60 is 0.166667, rounded to 0.17.
10 km/ 0.17 hours =
Change in momentum: finial momentum - initial momentum
Momentum = mass * velocity
Mass = 100g, same as 0.1kg
m(v-u) = 0.1(10-2) = 0.1(8)
The answer is 0.8Ns