When is the z-statistic used to estimate the population mean?a.When the population standard deviation is knownb.When the population standard deviation is unknownc.When the sample size is smalld.When the sample size is large

The formula for calculating the z-statistic is:a.(Sample mean - Population mean) / Sample standard deviationb.(Sample mean - Population mean) / Population standard deviationc.(Sample mean - Population mean) / Square root of sample sized.(Sample mean - Population mean) / Square root of population size

31.When can the z-test be used in statistical hypothesis testing?  A. When the measure of central tendency used for the raw scores is the median  B. When the raw scores are transformed from a nominal scale to a ratio scale  C. When the raw score population standard deviation is known  D. When the z-test standard deviation is known

In a study, a random sample of 20 patients was selected to estimate the average recovery time after a surgical procedure. The sample mean recovery time was 10 days, and the sample standard deviation was 2 days. If the population standard deviation is unknown, what should be used to estimate the population mean?a.z statisticb.t statisticc.F statisticd.Chi square tes

One difference between conducting a z-test and a t-test is that in the former... the population mean is known the variance is twice as big the population variance is known the standard deviation is half as big

12. According to the Central Limit Theorem, the sample standard deviation (𝑠) may be used as an estimate of the population standard deviation (𝜎) when the value of 𝜎 is unknown. Which of the following is the correct test statistic to be used for Central Limit Theorem?                  *A. p-testB. z-testC. t-testD. Pearson r