Charles is designing a study in which he combines the findings of and calculates the magnitude of all the combined results, otherwise known as a research like this can combine the statistical findings of individual studies to identify a(n)

empirical articles; meta-analysis; effect size      

Explanation:

Empirical research article: This is an article that describes the results of the research based on experiments or actual observations. This is an example of primary research.

Meta-Analysis: It refers to an experiment or research where the researchers inspect the results of a few previous studies, instead of doing new research with the subjects or the participants. This is a statistical procedure for merging data from various studies.

Effect size: This is a quantitative estimate of the immensity of the experimenter effect. Effect size is directly proportional to the relationship between two variables.

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the article must be ratified by three-fourths (38) of states within a proscribed deadline.

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