1.The remains of an old camp?re are unearthed and it is found that there is only 80% as much radioactive carbon-14 in the charcoal samples from the camp?re as there is in modern living trees. If the half-life of carbon- 14 is 5730 years, how long ago did the camp?re burn?
2. A bacteria population grows exponentially with growth rate k=2.5 how long it would take for the bacteria population to double its size?
3. The half-life of a certain drug in the human body is 8 hours how long it would take for a dose of this drug to decay to 0.1% of its initial level?