Sanitation inspection of cruise ships. To minimize the potential for gastrointestinal disease outbreaks, all passenger cruise ships arriving at U.S. ports are subject to unannounced sanitation inspections. Ships are rated on a 100-point scale by the Centers for Disease Control and Prevention. A score of 86 or higher indicates that the ship is providing an accepted standard of sanitation. The latest (as of Aug. 2013) sanitation scores for 186 cruise ships are saved in the SANIT file. The first five and last five observations in the data set are listed in the following table:

Ship Name Sanitation Score Adonia 96 Adventure of the Seas 93 AID Aaura 86 AID ABella 95 AID Aluna 93 f f Voyager of the Seas 96 VSP beta 100 Westerdam 98 Zaandam 100 Zuiderdam 96

a. Generate a stem-and-leaf display of the data. Identify the stems and leaves of the graph.

b. Use the stem-and-leaf display to estimate the proportion of ships that have an accepted sanitation standard.

c. Locate the inspection score of 69 (MS Columbus 2) on the stem-and-leaf display.