Managers of a sports arena's parking garage keep track of the duration of time customers park their cars there. Shown in the stem-and-leaf display below is a sample of 16 such parking durations (in minutes). Use the display to answer the questions that follow. Parking duration (minutes) 15 7 16 269 17 67888 18 039 19 3359 Key: 15|7 means a parking duration of 157 minutes. (a) What was the longest parking duration overall? (b) What was the shortest parking duration in the 160s? (c) How many customers had parking durations in the 150s? X