The correct answer is <span>3)

.
</span>
In fact, the total energy of the rock when it <span>leaves the thrower's hand is the sum of the gravitational potential energy U and of the initial kinetic energy K:
</span>

<span>As the rock falls down, its height h from the ground decreases, eventually reaching zero just before hitting the ground. This means that U, the potential energy just before hitting the ground, is zero, and the total final energy is just kinetic energy:
</span>

<span>
But for the law of conservation of energy, the total final energy must be equal to the tinitial energy, so E is always the same. Therefore, the final kinetic energy must be
</span>

<span>
</span>
We must decompose the displacement vector to find the new displacement to the west.
Adding all displacements to West, It comes:

If you notice any mistake in English, please let me know, because I'm not native.
Answer:
Time will be 2.13 sec
Explanation:
We have given that distance r = 14.3 cm =
Coefficient of static friction 
Angular acceleration is given by 
We know that frictional force is given by 
And centrifugal force is given by 
When coin just starts moving

We know that
, here
is angular velocity
According to first equation of motion we know that

As 
so 



