Galaxy is a collection of stars, gas, and dust bound together by gravity. The smallest galaxies may contain only a few hundred thousand stars, while the largest galaxies have thousands of billions of stars.
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The use of resources should be sustainable because many non renewable resources like coal and petroleum can be exhausted if they are over exploited.
Answer:
B. The random movement of pollen granules suspended in water.
Explanation:
Brownian motion is the irregular movement of particles suspended in a liquid or a gas, and it is usually caused when there is a bombardment of the particles by the molecules in the liquid or gas.
The Brownian motion who was named after Robert Brown, first experimented the random movement of pollen grains in water; therefore the movement of pollen grains or granules suspended in water.