21. The frequency distribution representing the number of frequent flier miles accumulated by employees at Brumley Statistical Consulting Inc. is repeated from Exercise 17. Frequent Flier Miles (000) O up to 3 3 up to 6 6 up to 9 9 up to 12 12 up to 15 Total Frequency 5 12 23 22825 50 a. How many employees accumulated less than 3,000 miles? b. Convert the frequency distribution to a cumulative frequency distribution. c. Portray the cumulative distribution in the form of a cumulative frequency polygon. d. Based on the cumulative relative frequencies, about 75% of the employees accumulated how many miles or less