A sample of participants took part in a hearing experiment. Among other things, the absolute hearing threshold (in decibels) wasmeasured for each participant. The measurements were as follows:
25, 22, 18, 35, 37, 34, 31, 27, 24, 21, 33, 33, 33, 30, 30, 30
Draw the histogram for these data using an initial class boundary of and a class width of . Note that you can add or remove classes from the figure. Label each class with its endpoints.