Answer:
If the speed would be doubled, the distance traveled by the vehicle will be FOUR times. It can be proved by 3rd equation of motion.
Step-by-step explanation:
When the brakes are applied, frictional force acts on the tires which decreases the speed. Eventually the car will stop. This frictional force is nearly independent of the speed hence by applying 3rd equation of motion, we can find the distance traveled.
2aS = Vf²-Vi²

For Vf=0
S=-Vi²/2a
Vi-new = 2*Vi
S-new = -(Vi-new)²/2a
S-new = -(2*Vi)²/2a
S-new = -4Vi²/2a
S-new = 4.S
Here
Vf= Final Velocity i.e. 0m/s²
Vi= Initial Velocity
a= Deceleration (Negative Acceleration)
S= Distance covered by vehicle