Answer:
Explanation:
From the question we are told that
The moment of inertia is 
The final angular speed is 
The time taken is 
The initial angular speed is 
Generally the average angular acceleration is mathematically represented as

=> 
=> 
Generally the torque is mathematically represented as

=> 
=> 
Answer:
Speed of light
Explanation:
The famous Einstein's equation is:

where
E is the energy
m is the mass
is the speed of light
In this equation, Einstein summarized the following fact: mass can be converted into energy, and the amount of energy released in such a process is given by the equation.
An example of application of this equation is the nuclear fusion process. In a nuclear fusion, two lighter nuclei combine into a heavier nucleus. However, the mass of the heavier nucleus is slightly less than the sum of the masses of the two original nuclei: some of the mass of the original nuclei has been converted into energy, accorging to the previous equation.
Jack Kilby invented the circuit
In order to change the direction and speed, a net external force is required. A net external force is an unbalanced force which will change the direction and gives the speed in the opposite direction. Hence, its an unbalanced force from the joey that pushes the car in the other direction due to which it the car starts to move back to Leah. Without, unbalanced force there is not change in the direction of the car's motion.
Hence, option B is correct.