A Researcher Wishes to Study the Relationship Between the Level

question 42

Multiple Choice

A researcher wishes to study the relationship between the level of background noise and mental concentration. The treatment (noise level) will have three levels: no noise, low-intensity noise, and high-intensity noise. the subjects are to be divided into three groups, and each group is to receive one of the treatments. He has available to him a set of 60 female volunteers and a set of 90 male volunteers. What experimental design strategy would help him eliminate the introduction of gender as a confounding variable? ​

• A)stratified sampling
• B)replication
• C)blocking
• D)systematic sampling
• E)double-blind trials

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Definitions:

Units Produced

The total quantity of products manufactured by a company during a specific period.

Total Variable Cost

The sum of expenses that vary directly with the level of production or sales volume; these costs increase as production increases and decrease as production decreases.

Units Sold

The total quantity of product items that a company has sold to consumers during a certain period.

Indirect Manufacturing Cost

Costs in the production process that are not directly tied to the physical production of goods, such as maintenance and utilities.