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Which of the following is the result of expanding the series

You buy 4 items that cost 2.69 14.45 8.05 13.95 what is the estimated total round to the nearest dollar

Identify all the cases where non-probability sampling is used when attempting to study the characteristics of a large city. studies on every subject in the population divide a population in groups and obtain a sample studies with a limited amount of time demonstrate existing traits in a population studies with the nth person selected