A Research Assistant Takes a Survey of Local High School

question 1

Multiple Choice

A research assistant takes a survey of local high school students who participate in after-school sports about whether they have suffered a concussion in the last 90 days. This is an example of which method of controlling extraneous variables?

• A) Random assignment
• B) Bias selection
• C) Random sampling
• D) Manipulation control

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Definitions:

Solar Water Heaters

Devices that convert sunlight into heat to warm water for residential and commercial uses, promoting energy efficiency.

Nonprice Competition

A strategy where businesses compete on factors other than price, such as quality, service, or brand image.

Product Differentiation

A marketing strategy that businesses use to distinguish their products from those of competitors.

Tacit Collusion

A situation where businesses indirectly coordinate actions without explicit agreement, often leading to market prices above competitive levels.