A cross section of Earth reveals a layered structure that has different thicknesses and densities. How do geologists know this?
A) from drilling and digging down into the various layers
B) from observing the characteristics of lava and gas issuing from volcanic vents
C) from observing the transit times through Earth of seismic waves generated by earthquakes
D) from comparisons with drill cores taken by robot spacecraft on Mars and Venus
C
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Suppose it is a winter night and at about 11 pm the air cools to the dew-point temperature and a
thick radiation fog develops. If the air continues to cool during the night, in 5 hours the dew point temperature will probably:a. decrease as the air becomes drier. b. decrease as the air becomes moister. c. increase as the air becomes drier. d. increase as the air becomes moister.
The record of an earthquake obtained from a seismic instrument is a(n) ________
A) seismograph B) seismogram C) P-S graph D) epitaph
Use the following map to answer this question.
Identify a volcano that is most likely to have both basalt and rhyolite as products of its eruption.
A. G B. H C. C D. F
In 1970, East Asia surpassed Western Europe as the US' chief trading partner
Indicate whether the statement is true or false