Why does earth rotate?

1. because earth is formed from cold gases collapsing due to gravity

2.because the matter in the nebula that formed earth was spinning

3.because earth forms more than 99% of the mass of the solar system

4.because the hydrogen atoms inside the nebula fused to form helium

The answer would actually be, because Earth is formed from cold gases collapsing due to gravity. The Solar System was formed when a huge amount of dust and gas began to collapse under its own gravity, and as the cloud collapse it started to spin causing the material within the cloud to gather into a swirl and then formed into planets and as the planets are formed they kept this spinning motion.

PLEASE MARK BRAINLIEST!!!

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.