Phebe-AnnHenry

Thank you so much.

Hello folks. Short history, my sister's always complaining about how hard her assignments are and lauding the fact that I went to college for music while she was more serious over me... anyway... I bet her that I could do one of her assignments and get as many, if not more of the answers correct. There are ten question and I've finished 8 but I'm stuck and 9 and unsure about 10. Please help. 9. Isotope X has a half-life of 10 days. A sample is known to have contained about 5 million atoms of isotope X when it was put together but is now observed to have only about 100,000 atoms of isotope X. Estimate how long ago the sample was assembled. Explain the relevance of this problem to the technique of radiometric dating. (I figure this involves some fancy formula. I confronted her about putting in something like this and she said she just gave me a random paper. I have no idea how to begin answering it but would appreciate learning. If you could show me how its done rather than just telling me the answer I'd love that). I think I can figure 10 out so won't bother you with that. Thank you