I believe the answer is A, temperature and number of particles are constant. Correct me if i'm wrong :)
Answer:
New moment of inertia will be
Explanation:
It is given initially angular velocity 
Moment of inertia 
Angular momentum is equal to 
Now angular velocity is decreases to 
As we know that angular momentum is conserved
So 

So new moment of inertia will be 
Answer: C
Frictional force
Explanation:
The description of the question above is an example of a circular motion.
For a car travelling in a curved path, the frictional force between the tyres and the road surface will provide the centripetal force.
Since the road is banked, and the cross section of the banked road is constructed like a ramp. The car drives transversely to the slope of the ramp, so that the wheels of one side of the car are lower than the wheels on the other side of the car, for cornering the banked road, the car will not rely only on the frictional force.
Therefore, the correct answer is option C - the frictional force.
Power is the energy transferred or "WORK DONE" in one second
B) It’s material moves due to convection currents.