Which newly independent african nation created a race classification system to enforce segregation?

Why don't all places on earth receive the same amount of direct sunlight at the same place?

The solstices and equinoxes, and the number of hours of daylight associated with each, are major factors in the seasons. use the drop-down menus to identify the month when each of these events occurs. the winter solstice in the northern hemisphere: an equinox in both hemispheres: the summer solstice in the northern hemisphere:

The earth's internal process which drives seafloor spreading is