The Degradation of Irrigated Soils Across the Once Very Productive

question 2

Multiple Choice

The degradation of irrigated soils across the once very productive "Fertile Crescent" of the Middle East was due primarily to _____.

• A)high calcium and magnesium levels in the irrigation waters
• B)high levels of calcium-containing salt in the irrigation water
• C)inadequate equipment and power to properly cultivate the soil
• D)poor internal drainage of the soils
• E)destructive wars in the region

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Definitions:

Independent Variable

A variable that is manipulated or changed in an experiment to observe its effect on the dependent variable.

Virtual Accidents

Simulated accidents within a digital environment, often used in safety training or the study of human responses to emergency situations.

Texting

The act of sending and receiving short text messages, usually through mobile phones or internet-based applications.

Placebo Effect

A phenomenon in which a fake treatment, an inert substance like a sugar pill, can sometimes improve a patient's condition simply because the person has the expectation that it will be helpful.