I think this one's B. energy and work are both measured in joules.
We have: Gravitational Potential Energy (U) = mgh
Here, m = 3 Kg
g = 9.8 m/s² [ constant value for earth system ]
h = 3 m
Substitute their values into the expression:
U = 3 × 9.8 × 3
U = 88.2 J
In short, Your Answer would be 88.2 Joules
Distance is 90km,time 1 hr
distance 2 is 82km,time 5 hrs
average speed=total distance travelled/total time taken.
90+82=172/5+1=6
average speed=28.7km over hour