<prompt> In a village of 1 lakh populations, among 20,000 exposed to smoking, 200 developed cancer, and among 40,000 people enexposed, 40 developed cancer. The relative risk of smoking in the development of cancer is -2010515  <response>: Relative risk incidence in exposedincidence of disease in non exposed Relative risk 1 no association between disease and risk factor 1;there is positive association between disease and risk factor Incidence in exposed 20020000 Incidence in nonexposed 4040000 Relative risk .01.001 10 Ref: Parks textbook of preventive and social medicine, 23rd Edition, Pg no: 78 