Answer:
Researchers typically use random assignment.
Explanation:
Random assignment is when a researcher uses chance to make sure all participants have the <em>same opportunity to be in either group</em> during an experiment. It is used to decide in which group the now selected participants will be in.
An example of random assignment is the<em> flip of a coin. </em>
They belong under logical appeal
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Geography has a profound effect on where civilizations settle. The earliest civilizations resided within river valleys, and used the area around them to create opportunities to benefit their growth. Mountains, rivers, and plateaus provided natural defenses, at the cost of movement and trade.
The right answer for the question that is being asked and shown above is that: "a decreasing birth rate and increasing life expectancy" Causes for the increase in the elderly population include: <span>a decreasing birth rate and increasing life expectancy</span>
