If by revolution you mean the spin on it's own axis this is more or less a perfect circle. If you are referring to it's orbit around the sun, this is elliptical, not a perfect circle.
The earth make's an oliptical revolution around the sun.
24 i think.
The surface of the earth is called the crust. I hope this is the answer you need.
half of earths layer
The molten iron and medals inside the earths core are the reasons for the earths magnetic core.
what causes changes to earths landform
The tectonic plates below earths surface shape earths landforms
the earths shape and its rotation
Weathering and erosion shape earths surface by changing earths surface by having extreme forces that change earth.
no they are not
sphere
Gyres
Uranus
A year.
Days & Years.
24 i think.
oval
oblong