To determine if the environment can affect sperm quality and production in cattle, a researcher randomly assigned 13 bulls to one of two environments. Six were raised in an open range environment while 7 were reared in a smaller penned environment. The following plot displays the sperm concentrations (millions of sperm/ml) of semen samples from the 13 bulls.

(a) Using the preceding graph to justify your answer, would the use of Student's t method be appropriate to compare the mean sperm concentrations under these two experimental conditions?
(b) How would your answer to (a) change if the data consisted of 60 and 70 specimens rather than 6 and 7?
(c) The Shapiro-Wilk test of normality yields P-values of 0.0012 and 0.0139 for the Open and Pen data, respectively. How do these results support or refute your response to part (a)?
(d) How might a transformation help you analyze these data?

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