Answer:
I = 0.287 MR²
Explanation:
given,
height of the object = 3.5 m
initial velocity = 0 m/s
final velocity = 7.3 m/s
moment of inertia = ?
Using total conservation of mechanical energy
change in potential energy will be equal to change in KE (rotational) and KE(transnational)
PE = KE(transnational) + KE (rotational)

v = r ω




I = 0.287 MR²
If you only know its speed, that's not enough information to catch it. You could even chase it at DOUBLE that speed, and you'd never catch it if you were chasing in the wrong direction.
You also have to know the DIRECTION the runaway car is going, so that you can chase in the same direction.
Now that you know its speed AND direction, you know its velocity. You need that information to have any chance of catching it.
Answer:
62.5 %
Explanation:
Let the initial intensity of unpolarized light is Io.
After first polariser the intensity of light becomes I'.
So, 
Now it passes through another polariser. The angle between the first polariser and the second polariser is given by Ф. The intensity is I''.
According to the law of Malus

Here, Ф = 30 degree

The percentage change in the intensity is given by

= 62.5 %
That will be A melting a substance that's because the rest are examples of chemical changes and also its the same thing but in a different form.