In the last 20 years geologists have begun measuring accumulation of Helium (He) in some minerals because these minerals can retain He at temperatures up 100-200°C. The "date" gives a time when the material cooled below the temperature where the helium began to be retained, which is related to the depth of the material. Where do you think the He comes from that allows this technique to work?
A) alpha decay of some radioactive element
B) beta decay of some radioactive element
C) the sun
D) the atmosphere, like carbon-14
A
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Wild turkeys, peregrine falcons, and snowy egrets are examples of birds that have
A) are extinct despite extensive efforts to save these species. B) very few individuals restricted to just a few small populations. C) all been severely impacted by the spread of the bird flu. D) recovered significantly since gaining legal protection.
Alcohol and pickling solutions were probably widely developed because they
A. Have more interesting flavors than other solutions for seasoning B. Are effective insecticides in the home C. Preserve food due to their pesticidal properties D. Neutralize toxins in foods E. All of these are good reasons why alcohol and pickling solutions were used
Which of the following is currently a problem with modern-day weather predictions?
A. There are regions of the world where observations are sparse. B. Computer forecast models make assumptions about the atmosphere that are never correct. C. Computer models inadequately interpret the influence of the surface on the weather. D. The distance between grid points on some models is too small to pick up storm systems.
One important result of orogeny is that continental crust becomes thicker.
Answer the following statement true (T) or false (F)