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krepp
A certain radioactive material is known to decay at a rate proportional to the amount present. If three are 256mg of the material present initially and after 4 hours it is observed that hte material has lost 6.25% of its original mass, find1. an expressision for the mass of the amterial m, remaining at any time t 2, the mass of the material after 8 hours 3. the time, to the nearest hour, at which the material has decayed to one-quarter of its initial mass.