Verified answer

work = force * distance

force = mass * acceleration

to find work, we need force and distance. first, we find force.

all calculations must be done in meters per second, not miles per hour

15 mi/h = 6.71 m/s

force = mass*acceleration

force = 800kg*1.2m/s^2

force = 960N

next, we find the distance.

distance = starting velocity + acceleration*(time)^2

distance = 6.71 + (1.2)(10)^2

distance = 126.71m

work = force * distance

work = 960N * 126.71m

work = 121641.9 Joules