Which region currently presents the most mysteries to scientists?
A) the low velocity zone in the upper mantle
B) the transition zone
C) the lowermost mantle
D) discontinuities at 410 and 660 km
Question 2
Which of the following is not a reason that scientists have inferred that the core consists mostly of iron?
A) Iron is the only common element that accounts for the high density of the core.
B) Liquid iron in the core can explain Earth's magnetic field.
C) Molten iron's typical movement accounts for the wobbly rotation of Earth on its axis.
D) Some meteorites consist mostly of iron and appear to be likely analogs for planet cores.
Jacob, Monod, and Pardee's hypothesis for the function of the lacI region
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