FORESTRY
AGRICULTURAL STATISTICS AND ECONOMICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Researchers studying acid rain measured the acidity of precipitation (response variable) in an isolated wilderness area in Colorado and the duration of rain in weeks (explanatory variable). The researchers reported that there was a strong negative linear association between “acidity” of precipitation and duration of rain in “weeks”. Determine which of the following is a possible measure of the relationship.
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r = 0
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r = 1.0
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r = 0.92
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r =-0.24
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r =-0.95
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Explanation:
Detailed explanation-1: -Normal, clean rain has a pH value of between 5.0 and 5.5, which is slightly acidic. However, when rain combines with sulfur dioxide or nitrogen oxides-produced from power plants and automobiles-the rain becomes much more acidic. Typical acid rain has a pH value of 4.0.
Detailed explanation-2: -As this diagram shows, pH ranges from 0 to 14, with 7 being neutral. pHs less than 7 are acidic while pHs greater than 7 are alkaline (basic). Normal rainfall has a pH of about 5.6-slightly acidic due to carbon dioxide gas from the atmosphere.
There is 1 question to complete.