38 Shell lengths of sea turtles. In a Aquatic Biology (Vol.

9, 2010) study of green sea turtles inhabiting the Grand Cayman South Sound lagoon, the curved carapace (shell)

lengths of these turtles has a distribution with mean m = 50 cm and standard deviation s = 10 cm . In the study, n = 76 green sea turtles were captured from the lagoon; the mean shell length for the sample was x = 55.5 cm. How likely is it to observe a sample mean of 55.5 cm or larger?