
Answer:
Explanation:
We shall apply law of conservation of momentum to know the Speed of northward moving vehicle before collision to check the veracity of driver's statement .
Let v be the velocity of composite mass after collision
Applying law of conservation of momentum in north direction
m vâ‚‚ = 2m v sin55.08
Applying law of conservation of momentum in east  direction
m x 13 = 2m v cos55.08
Dividing these two equations
vâ‚‚ / 13 = tan55.08
vâ‚‚ = 13 Â tan55.08
= 18.62 m/s
= (18.62 x60 x 60) / 1000
= 67 km/h
= 67 x 5/8 mi/h
= 42 mi/h
So he is lieing.