Which of the following statements are true? a) the sample mean is an unbiased estimate of the population mean. b) the z-critical value is an estimate of the population mean. c) the t-critical value is an estimate of the population standard deviation. d) the sample standard deviation is an unbiased estimate of the population standard deviation. e) none of the above.

e) None of the above.

Step-by-step explanation:

a) The sample mean is an unbiased estimate of the population mean.

False. Population mean can be estimated with a margin of error around the sample mean in a specified confidence level

b) The z-critical value is an estimate of the population mean.

False. z value is a conversion of values in standard normal distribution

c) The t-critical value is an estimate of the population standard deviation.

False. Similar to z-score t-value is a conversion in t-distribution.

d) The sample standard deviation is an unbiased estimate of the population standard deviation

False. It is a biased estimate.

d≈7.07in

step-by-step explanation:

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