2. Find the median and mode for the set of numbers:
a. 2, 5, 6, 8, 7, 2, 3, 9, 12, 10, 11, 6, 5, 18
b. 18.5, 21.7, 19.3, 25.4, 16.7, 28.5, 17.2, 20.1