
I need to know the document font size used in index.tex.  This font size
is in points, and can be found in the options of the 'documentclass' command.
If the documentclass does not have an explicit font size, the value is 10.

Dirty trick:  By entering a number here that is a bit *less* than the actual
point size in index.tex, you can get mathematics appearing inside lines of
text to become somewhat *bigger* than the surrounding text.  This trick
allows you to make fine adjustments to the size of the math images.
