A work-standards expert observes the amount of time required to prepare a sample of 10 business letters in an office, with the following results listed in ascending order to the nearest minute: 5, 5,...

A work-standards expert observes the amount of time required to prepare a sample of 10 business letters in an office, with the following results listed in ascending order to the nearest minute: 5, 5, 5, 7, 9, 14, 15, 15, 16, 18 . Determine the (a) mean, (b) median, and (c) mode for this group of values.