Why are there extra "?" in my pages?

In reviewing the pages getting ready to take the new site live, I have noticed some pages insert a "?" in odd places.  For reasons that I do not completely understand, at least on my test system, the browsers are inserting this ? where the browser encounters any character it does not understand.  This appears to occur where there is poor html editing in the sense of closing tacks still existing where the opening tag has been removed or where there is too much white space.  Most of the instances appear to arise where documents prepared elsewhere have been imported.  My generation learned to put two spaces between sentences and I genearlly still do this by habit.  This seems to be the major casue of this error.  I must admit some puzzlement here since this did not occur (to my kinowledg) under older browsers on the static html pages which ignored extra white space. 

I have edited some of the pages and have spot checked each study but I may have missed some of the instances where these errors arise.  If you find any pages with the errors, drop me an email, use the contact page, or add a comment and I will attempt to eventually correct them.

Jim A.