In a study of milk production in sheep (for use in making cheese), a researcher measured the three-month milk yield for each of 11 ewes. The yields (liters) were as follows:
56.5 89.8 110.1 65.6 63.7 82.6 75.1 91.5 102.9 44.4 108.1
(a) Determine the median and the quartiles.
(b) Determine the interquartile range.