(Q009) Magnetic reversals a. happen slowly as the magnetic poles wander and finally cross the equator. b. are localized phenomena that are recorded differently in the rock record at various locations. c. are caused by lightning strikes and/or chemical reactions. d. reflect changes in the direction of the flow of molten iron in the Earth's outer core.

1. crust 1 the metallic layer at the earth's center 2. inner core 3 the firm layer between the crust and the asthenosphere 3. lower mantle 2 the layer surrounding the inner core 4. asthenosphere 4 the semi-solid layer between the top layer and the upper mantle 5. upper mantle 5 the layer between the asthenosphere and lower mantle 6. top layer 6 the earth's outermost layer 7. outer core 7 the hottest part of the mantle