if the mean of the samples are usually distributed then i am asking if the mean of the samples is when do you do a parametric t test on two samples what is normal distribution in statistics when do you test randomly for the distribution of a sample why are two samples of data normally distributed how to test differences between two sample why is a histogram normally distributed why test for differences in normal and unnormal distributions? which condition requires a parametric t-test for statistically based sampling? why is t test used for normal distribution why would you test for normally distributed data why test normally distributed how to find the difference between a normal distribution of two samples? why is it usually necessary to use a parametric two sample test for the mean why is it useful to test normally distributed data? why do you use the parametric t test to check whether the sample is normally distributed when are two data points normally distributed why is it important to test normally distributed data why would an expected variance be used in a two sample t-test are samples normally distributed