Answer:
Acceleration will be 
Explanation:
We have given initial speed of the car is 70 km/hr
We know that 1 km = 1000 m
And 1 hour = 3600 sec
So 
It is given that car stops in 12 sec
So final speed of the car v = 0 m/sec
Time t = 12 sec
From first equation of motion v = u+at
So 
( negative sign indicates that speed of the car will constantly decrease )
Acceleration due to gravity
Answer:
The Kinetic Energy decreases. The Total Energy stays the same
Explanation:
The TE stays the same, so if PE increases then KE will decrease.