=+12.25 ● Data consistent with summary quantities given in a paper that appeared in the British Medical Journal

(“Cigarette Tar Yields in Relation to Mortality from Lung Cancer in the Cancer Prevention Study II Prospective Cohort” [2004]: 72–79) are shown in the accompanying table. Suppose that the table was constructed by classifying individuals in a random sample of smokers according to gender and the age at which they began smoking. Do