Upon what basis were the upper and lower boundaries of the Mesozoic Era defined?
A. the discovery that a meteoroid impact may have killed the dinosaurs
B. dramatic changes in the color of the rocks from green to tan
C. major episodes of mountain building
D. abrupt changes in the types of fossils, representing mass extinctions
Answer: D
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Biodiversity hotspots are
A. typically near coral reefs and have low rates of endangered species. B. cover more than 25% of the earth's land surface. C. areas especially rich in plant species that are found nowhere else and are in great danger of extinction. D. freshwater habitats threatened by invasive species. E. only found in habitat islands near volcanoes.
Given the following generic chemical reaction, which is the reactant? X ? Y
A) Y is the reactant. B) X is the reactant. C) ? is the reactant. D) Both X and Y are the products. E) Both X and Y are the reactants.
The majority of the United States lies within a(n) ____ wind belt
A) westerly B) easterly C) northerly D) southerly
In what region/country are the wages of women equal to those of men? (Where is there no gender gap?)
A) Australia B) Latin America C) Sub-Saharan Africa D) United States E) the wages of women are lower in all of the above