Promised you a note on how to fit an exponential. I also included a section on how to save yourself some time on data taking. If the concept of a chi-square is new to you, please let me know and we can work on that. Also, if this write-up is completely baffling to you, let me know. (p.s. I don't expect you to get the thing the first time you read it... I.e. I didn't say a lot of things explicitly, and you may have to think a minute to realize what I'm getting at.)