For extent of carinal resection in DB12,

(a) select intervals for a tally,

(b) tally the data,

(c) find the median, and

(d) convert the tally into a relative frequency distribution.

(e) Comment on whether the distribution appears by eye to be near normal. If not, in what characteristics does it differ?

(f) Give a visual estimate (without calculation) of the mean and mode. How do these compare with the median found in (c)?