A group of concerned citizens was worried that their local water supply might be contaminated with naturally occurring arsenic. They decided to purchase a home arsenic monitoring kit and tested well water in their local area. After analyzing the data (shown below), the citizens wrote a letter to the editor of a local newspaper arguing that their data proved that the water supply is contaminated. They demanded immediate government action to address the problem. The local water board again tested the wells using their official water testing instruments and found average concentrations of 8.1 +/- 0.2 micrograms per liter. Assume the water board's reported measurements are the accepted value. The maximum permitted level of arsenic in water supplies is 10 micro-grams per liter. 

src="https://sciemce.com/media/4/ppg__1020817191133__f1q510g1.jpg" alt="" style="vertical-align: 0.0px;" height="119" width="470" /> Which of the earth-system scientist's roles is best illustrated by this paragraph?

A. Informing society
B. Use of earth resources
C. Alerting the public of natural hazards
D. Health of the environment

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Answer: A

Environmental & Atmospheric Sciences

What is the Younger Dryas?

A. A gradual warming from 20,000 to 15,000 years ago B. A warming event that occurred about 55 million years ago C. An abrupt cold snap that began about 15,000 years ago D. Another name for the Little Ice Age

Small turbines have been placed in the Gulf Stream to harness this major ocean current

Indicate whether the statement is true or false

Net accumulation of a glacier results in glacial advance

a. True b. False Indicate whether the statement is true or false

You observe a distinct, red sandstone rock body about 50 m thick that is depositionally overlain by a red shale with interbedded gypsum and you follow this boundary in the rock bodies for 1 km until you cross a fault which has displaced the boundary

between the two rock bodies. You walk along the fault and see a boundary between a 50 m thick red sandstone and overlying red shale interbedded with gypsum. You conclude ________. A) the second exposure of sandstone, shale and gypsum correlates to the first, and the boundary between the sandstone and shale is the same stratigraphic horizon B) this is impossibly complex; the fault broke up all the rocks C) this new exposure of sandstone, shale and gypsum must be a different age rock unit D) the stratigraphic section must have been inverted by the deformation; the rocks are upside down