That isn"t the right answer the correct answer is B.
Answer:

Explanation:
From the question we are told that:
Mass 
Deviation 
Time 
Generally the equation for moment of inertia is mathematically given by



Answer:
19 m/s
Explanation:
The complete question requires the final speed to be calculated.
Velocity is the rate and direction at which an object moves. Acceleration is the rate of change of velocity per unit time and can be calculated by the difference in velocity over a given time.
For this question, first the unknown acceleration must be calculated and used to determine the final velocity
Step 1: Calculate the acceleration




Step 2: Calculate the velocity using the acceleration calculated above



Answer:
1- For the track B. The potential energy is the same for the two cars, but because of the slope of the track, the car B earn kinetic energy faster. The gravitation acceleration of the cars will be g•sinθ, and the angle of the track B will have a bigger value for sinθ
2- The conservation of energy applies because the roller coaster is a closed track. When a car climb the track, it earn GPE, which is given by mgh, when it get down in the track, it transform GPE in KE, which is given in 1/2mv².
3-
Position of car (m) GPE KE GPE + KE
top (30m) 60000 0 60000
bottom (0m) 0 60000 60000
halfway down (15m) 30000 30000 60000
three-quarters way down 15000 45000 60000
It stands for Unified Computing System
I hope I helped :3