Im pretty sure you are talking about Sahel. If not my bad.
Answer:
The different phases of the moon are caused by the angle that sunlight is reflected of off the moon towards earth. As the moon rotates around earth the angle changes and we see different fractions of the moon. When the earth is completely between the moon and the sun there is a dark new moon, and when the moon gets to a point in its orbit where the entire surface facing the earth reflects light, then it is a full moon.
Explanation:
the answer is 3/C.) galaxies spin faster than they should, based on their visible matter
Pollution. When there are too many gasses in the atmosphere it contributes to global warming
Hikers, campers, snow skiers, city and county planners, the Fish and Wildlife Service, Forest Service, miners, loggers, highway planners and construction workers, travelers, surveyors, geologists, engineers, and scientists are just a few of the people who use topographic maps