A 1.5 kg book falls off a table that is 1.5 m from the floor. at what time will the book land on the floor? ​ 1. 2.5 seconds
2. 0.25 seconds
3. 1.0 seconds
4. 0.55 seconds

a.) travels faster in solids because the particles are closer together.

air is a gas water is a liquid

as we probably am aware that our atmosphere or air have various levels, each level has different gasses, and each gas has another porousness. at the point when the light originates from lower porousness to higher penetrability, it alters its course. with the goal that implies that when the light originates from the moon to the earth, it alters it's course a lot more occasions. it essentially implies that the state of the light piece of the moon is changed on the earth.

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joke:

h o h o hope you have a merry christmas!

3. dark matter

empty space could also be a simple vacuum