since we were given the key ( how it should be sort out or used )
then we get all the numbers out which are:
21, 23, 30, 32, 32, 35, 43, 44, 46, 48, 49, 49, 50, 52, 52, 53, 55
then we go ahead to answer the questions:
a) Range = highest number minus Lowest number
55 - 21 = 34
b) 17 (by counting all individual ages ).
c) Median = the middle age
(but before that, we must arrange the ages either a cording to their sizes either from biggest to smallest (descending order) or from smallest to biggest (ascending order)
so we arrange in ascending order but the numbers are already arranged so we don't have to stress ourselves:
Median = 46 (the number in the middle ).
Hope you ace your tests, Good luck ✅.