Answer:
The longest time period is eons.
Answer: The earth's spin axis is tilted with respect to its orbital plane.
Explanation:
This is what causes the seasons. When the earth's axis points towards the sun, it is summer for that hemisphere. When the earth's axis points away, winter can be expected.
Answer:sand dunes
Explanation:
They are man made barriers, made of sand, to protect the coast from erosion from the incoming waves. They also help to control flooding from storm surge.
During the early earth, when photosynthesis has not yet evolved, there were only negligible amounts of free oxygen in the atmosphere. It was said that the Earth's atmosphere had no free oxygen then. This is about 3.5 billion years ago.
Answer:
The germinate stage refers to the time from fertilization.through the development of the early embryo until implantation completed in the uterus.