Kinetic energy depends on the mass and the speed of a moving object.
If the speeds are equal, then the rick with more mass has more kinetic energy.
Assuming the driver starts slamming the brakes immediately, the car moves by uniformly decelerated motion, so we can use the following relationship

(1)
where
a is the deleceration
S is the distance covered after a time t

is the velocity at time t

is the initial speed of the car
The accident is 80 m ahead of the car, so the minimum deceleration required to avoid the accident is the value of a such that S=80 m and

(the car should stop exactly at S=80 m to avoid the accident). Using these data, we can solve the equation (1) to find a:

And the negative sign means it is a deceleration.
B. Refraction because objects refract in water
Question 1
To find centripetal acceleration, use the formula : centripetal acceleration = v^2/r
so answer would be (3.71)^2/42.85=0.32 (2d.p.)
Question 2
Force =ma
a= (9.98)^2/31.77=3.1350
Force= 3.1350 * 56.63 = 177.54 (2 d.p.)