Answer:
B) A volcanic lava flow cools and hardens on the surface.
Explanation:

The primary source of energy in a food chain is Sun, because producers are the ones that prepare food by themselves and that food is then passed on to higher levels in food chains. And as the producers make their from Sunlight, the primary source of energy in food chain is <u>Sunlight</u> .
The atmosphere and the hydrosphere.
Answer:
This biome features forests and grasslands that go dormant during the winter.
This biome features high levels of biodiversity and is located near the equator.
This biome features a level of permafrost and a short growing season during the winter.
This biome features tropical grasslands and is located near the equator.
Eukaryotic cells have one nucleus inside a membrane.
Prokaryotic do not have a membrane bound nucleus nor <span>mitochondria.
Also, please note the following:
Mitochondria is the powerhouse of the cell
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