38.) In a research setting, it is more common to use t-tests than...

38.)       

In a research setting, it is more common to use t-tests than z-tests because

		Typically the population mean is unknown.
		Typically the population standard deviation is unknown.
		They are more accurate since sample size is taken into account when determining critical values.
		Typically the sample mean is unknown.
		"t" comes before "z" in the alphabet