It caused legislators who were writing new legislation to reject language that could be construed as permitting racial discrimination.
It made it more difficult for commercial businesses to practice racial discrimination.
The Earths magnetic field is generated as the molten iron of the Earths outer core revolves around its solid inner core. When surges in the molten iron occur, magnetic tempests are created. At the Earths surface, these tempests can be detected by changes in the strength of the Earths magnetic field. For reasons not fully understood, the field itself reverses periodically every million years or so . During the past million years, for instance, the magnetic north pole has migrated between the Antarctic and the Arctic.
Clearly, geophysicists who seek to explain and forecast changes in the field must understand what happens in the outer core. Unlike meteorologists, however, they cannot rely on observations made in their own lifetimes. Whereas atmospheric storms arise in a matter of hours and last for days, magnetic tempests develop over decades and persist for centuries. Fortunately scientists have been recording changes in the Earths magnetic field for more than 300 years
24. In the passage, the author is primarily concerned with
analyzing a complicated scientific phenomenon and its impact on the Earths surface features
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