Write as a Number

question 24

Multiple Choice

Write as a number.
-Round 21,430 to thousands.

• A) 21,000
• B) 31,000
• C) 22,000
• D) 21,100

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Definitions:

External Validity

The extent to which the findings of a study can be generalized to other settings, populations, and time periods beyond the original conditions of the study.

Independent Variable

In research and experimentation, it is the variable that is manipulated or changed to observe its effect on a dependent variable.

ABAB Design

A research method involving repeated measurements over time where conditions are alternated to observe the effect of an intervention.

Single-subject Experiment

A research design in which interventions are tested on a single individual, allowing for detailed observation of effects over time and control over variables affecting the outcome.