Answer:
6.46393559312 m/s²
Explanation:
Time taken to cover 56 m

Distance covered in 0.42 seconds

From equation of linear motion


The minimum acceleration is 6.46393559312 m/s²
Answer:
B: Energy that is transformed is neither created or destroyed
Explanation:
The car at 60 kph has 9 times more kinetic energy than the car traveling at 20 kph. This assumes that both cars have the same mass. Kinetic energy depends on the square of thee speed so if one car is going 3 times faster, its kinetic energy will be 3^2 ( = 9 ) greater. The car going at 60 kph will have 4 times the KE of the car going at 30 kph ( again assuming that the cars have the same mass.)