The Proterozoic comprises what percentage of geologic time?
a. 12 percent d. 42 percent
b. 19 percent e. 65 percent
c. 35 percent
D
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Select the choice that correctly states the best priority for use of non-renewable resources, such as metals and plastics, from the environmentally sustainable perspective
a. recycle, reuse, reduce b. reuse, reduce, recycle c. reduce, reuse, recycle d. reduce, recycle, refuse e. repurpose, recycle, remake
Taking a refillable coffee cup to the office and using it instead of throwaway cups is an example of ____.
A. retooling B. reducing C. reusing D. repurposing E. recycling
Strontium-90 is a radioactive isotope which is particularly hazardous. Which of the following statements is true about an atom of strontium-90?
A) It contains 52 neutrons. B) It contains 52 protons. C) It contains 90 neutrons. D) It contains 90 protons.
Which U.S. region is made up of a series of high-angle normal faults producing nearly parallel mountain ranges?
A) Appalachian Mountains B) Basin and Range Province C) Colorado Plateau D) Valley and Ridge Province