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Radiocarbon dating can be usacao3ac9 k- 8x55 grw)tn-rw dec) lonz, +:h17kpmscsd to estimate the age of an artifact made of wood. Archeologists take a sample of wood from the artifact and measure the ratio,r, of Carbon-1414 in the sample to Carbon-1+kp1)hoslc z,c sm7: n414 in a living wood. The age, t, in years, is then estimated by using the equation
t=−$\frac{6000}{ln2}\times$lnr,[Age Model]
where 0.01A team of underwater archeologists found an ancient wooden shipwreck deep down in the Black Sea. A sample of wood is taken from the shipwreck to determine its age.
1.Find the age of the shipwreck if r=0.75.
In all wood samples, Carbon-14 decays over time. If r<0.01, there is insufficient amount of Carbon-14 left in the sample wood for its age estimate calculated by the age model to be reliable. t ≈
2.Find the oldest sample of wood for its age estimate found by the age model would just cease to be reliable. Give your answer to the nearest10000 years. t ≈
3.Using the age model, express r in terms of t.
4.Hence find r when t=7500, giving your answer correct to 2 decimal places. r ≈
