Refer to the diagram shown below.
The net force acting on the vehicle is
F - R = 1060 -1010 = 50 N
The distance traveled is 21 m. Because the force is constant, the work done is
W = (50 N)*(21 m) = 1050 J
Assume that energy is not dissipated by air resistance or otherwise.
Conservation of energy requires that W = KE, where KE is the kinetic energy of the vehicle.
The KE is
KE = (1/2)*(2000 kg)*(v m/s)² = 1000v² J
Equate KE and W to obtain
1000v² = 1050
v² = 1.05
v = 1.025 m/s
Answer: 1.025 m/s
