Carbon 14 is used to determine the age of organic material. The procerdure is based on the formationof .^(14)C by neutroncapture in the upper atmosphere. ._(7)^(14)N + ._(0)^(1)n rarr ._(6)^(14)C + ._(1)n^(1) .^(14)C is abosorbed by living organisms duringphostosythesis. The .^(14)Ccontent is constant in living organismsonce theplant or animal dies, the uptake of carbon dioxide by it ceases and the level of .^(14)C in the deadbeing, falls due to thedecay which.^(14)C undergoes. ._(6)^(14)C rarr ._(7)^(14)C+ beta^(-) The half-life period of .^(14)C is 5770 years. The decay constant (lambda) can be calculated by usingthe following formula lambda = (0.693)/(t_(1//2)) The comparison fo the beta^(-)activity fo the dead matterwiththat of the carbon still incirculation enables measurement of the period of the isolation the materail form the livingcycle. Themethod however, ceases to be accurate ever periodslonger than 30,000 years. The proportaion of .^(14)C to .^(12)C living matter is 1:10^(12). What should be the age of fossil for meainingful determination of its age?