Explanation:
The mean angle is all the angles added up together then divided by how many angles they were. For example:
I have four angles 44°, 37°, 29° and 67°, what I would do is add them all up together, i.e, 44+37+29+67, which equals to 180. Then I would divide 180 by how many angles they were, so I would do 180÷4 which equals to 45. So the mean angle would be 45°, that's how you find the mean, hope that helps.
The southern part, because the altitude increases as you go south in Egypt and leads into the Ethiopian highlands
The last option best shows a meteorite.
Meteorite definition: A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon.