An all-terrain vehicle of 4000 kg mass moves up a 13o slope at a constant velocity of 6.00 m/s. The rate of change of gravitational potential energy with time is
PE = m g h
d PE/dt = m g dh/dt
h = 6 t sin 13
dh/dt = 6 sin 13
so
d PE/dt = 6 m g sin 13