These questions were taken from the 1996 final exam. The University Testing Service rated all these questions as difficult and of medium effectiveness. Geologists have discovered long, generally straight chains of volcanic islands within ocean basins that get progressively younger or progressively older depending on the direction of travel along the volcanic chain. The Hawaiian Islands are an example of such a chain. Geologists have learned about the appearance and composition of mantle rocks from several sources.
Magnetic fields are proportional to the size of the planet .
Jupiter is much larger than the Earth. Magnetic fields are better developed in Planets with cooler average temperatures. Jupiter is more than twice as far from the Sun as the Earth and there for in a cooler part of the Solar System. Magnetic fields are stronger in the gas giants because of the combination of methane and ammonia found in the outer layers of Jupiter. Magnetic fields are stronger in those planets that spin faster.