The number of police calls a small police department received each month is shown in the frequency distribution.

Class limits                             Frequency
39.9–42.8                                                 2
42.9–45.8                                                 2
45.9–48.8                                                 5
48.9–51.8                                                 5
51.9–54.8                                               12
54.9–57.8                                                 3

a. Construct a percentile graph.
b. Find the values that correspond to the 35th, 65th, and 85th percentiles.
c. Find the percentile of values 44, 48, and 54.