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\Large
\noindent
Two last things:

(1) If the file says to install a graphics package
like {\tt graphicx}, it is possible to make a picture with a graphics
program, save it in {\tt .png} format (``portable network graphics'')
and have it appear in your document.  (The {\tt .jpg} format works, 
too, but the images seem ``smudged''.)  With a Mac, your pictures
should be in ``encapsulated PostScript'' {\tt .eps} format.

\centerline{\includegraphics[scale=.7]{notes18a.png}}

\centerline{\includegraphics[scale=1.2]{notes18a.png}}

\centerline{\includegraphics[scale=1.2]{notes18a.jpg}}

(2) After you have first typed the {\tt .tex} file and try to run it
through \LaTeX, you certainly will have made errors, and the program will
tell you where and what it {\it thinks} the first error is and say, with a
question mark, ``Now what?''  Reply with an x (and a carriage return) to
get back to the command prompt, and edit the {\tt .tex} file.

\end{document}


\centerline{\includegraphics[scale=]{.png}}