Hello Professor,

you mentioned that you didn't know that it was possible to add error bars
in Excel, I thought I'd explain how.

After plotting a set of data on a plot, right clicking on the data set in
the plot and selecting "Format Data Series" (naming and access might vary
across Excel versions), then going to tabs that say "X Error Bars" and "Y
Error Bars" will allow you to add error bars of constant or user specified
value to either or both sides of the data on that specific axis.
I've used this option in my lab data analysis with David Williams, where we
had a set of measurements each with an associated different error value, by
using the custom error bar option I was able to enter a different value
error bar for each measurement by selecting a column of data.

Excel also has a Trend line option for Power, Linear, Poly, Log, etc line
fitting.

-- 
Andrey Kuznetsov
High Energy Particle Astrophysics
Natural Science 2 Room 314
UCSC
akuznet1@ucsc.edu