Answer: The answer is option A.
Explanation: Particles of matter are packed more loosely in the ground than in the air. This is true because it doesn't have thig like buildings and people stopping the sound waves.
God is good man what can you say but its 18.66x30301=362728
The cooling on earth's surface (extrusive) makes a molten rock to become glassy. The lava cools so fast that crystals don't have time to form, which makes it glassy. Hope this helps!
Copper because it contains alot of electricity
Answer:

Explanation:
Consider two particles are initially at rest.
Therefore,
the kinetic energy of the particles is zero.
That initial K.E. = 0
The relative velocity with which both the particles are approaching each other is Δv and their reduced masses are

now, since both the masses have mass m
therefore,

= m/2
The final K.E. of the particles is

Distance between two particles is d and the gravitational potential energy between them is given by

By law of conservation of energy we have

Now plugging the values we get



This the required relation between G,m and d