Physics problem in work, power and energy

A truck weighing 1000 kgf changes its speed from 36 km/hr to 72 km/hr in 2 minutes . Calculate the
(1) work done by the engine
(2) and its power
Take g as 10m/s^2
Please tell me how to solve this problem and show the working as well
:)

72 km/h = 20 m/s
36km/h = 10 m /s

Work done by the engine is the change in kinetic energy of the body.

= 0.5 * 1000*( 20^2 – 10^2) = 150000 J
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Power = work /time = 150000/ (2*60) = 125 J/s = 1250 W
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These questions are so old I can't remember them anyway:
(1) W=Fxd
F is force
d is distance
F=mxg
F=1000x10
F=10^4
V=m/s m=Vxs (m is distance in meters)
V1 is 36x1000/3600
v2 is 72x1000/3600

V=Vf-Vi
V=V2-V1

M=Vx2x60

W=Fxd

(20) P=W/t


P=W/2x60




I hope i am totally correct :P