Answer:
<h2>Gravity :</h2><h3>the force that attracts a body towards the centre of the earth, or towards any other physical body having mass.</h3>
<h2>Solar day</h2><h3>A solar day is the time it takes for the Earth to rotate about its axis so that the Sun appears in the same position in the sky.</h3><h2> or</h2><h3>It is the time between successive meridian transits of the sun at a particular place.</h3>
Not possible. The air is actually able to travel sound throughout itself without any difficulties. I believe, air actually brings sound closer to the people farther away ; It really helps to stretch sound.