I have to figure out the minimum number of surveys needed to attain a confidence level of 95%
I have several organzations, each with a different population. For example:
Arizona: 523
New England 1,227
Washington: 744
Colorado: 2,333
What would be the minimum number of completed surveys in each to have a confidence level of 95%?
I believe I need to calculate the mean and standard deviation, but I'm not sure how that works in practice.
Thanks for your help.

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