Explanation:
It is given that,
Mass of person, m = 70 kg
Radius of merry go round, r = 2.9 m
The moment of inertia, 
Initial angular velocity of the platform, 
Part A,
Let
is the angular velocity when the person reaches the edge. We need to find it. It can be calculated using the conservation of angular momentum as :

Here, 


Solving the above equation, we get the value as :

Part B,
The initial rotational kinetic energy is given by :



The final rotational kinetic energy is given by :



Hence, this is the required solution.
Answer:
Density is the mass to volume ratio of an object.
> It tells you how compact the mass is.
> Density = mass/volume
The density of water is 1 g/ml or 1 kg/L or 1000 kg/m3
• If an object has a density less than that of water, it
will float.
• If an object has a density more than that of water, it
will sink
Explanation:
hope this helps some
Well i think the best answer would be A