% Bernd Berg Sep 01 2017.
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\centerline{\bf Special and General Relativity (PHZ 4601/5606) Fall 2017 
Solutions} \bigskip

\centerline{\bf Set 2} 

% \begin{figure}[tb] % \vspace{5pc}
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% \caption{for assignment~14.} \label{fig_lader} \vskip -10pt
% \end{figure} \centerline{Potential as function of $z$.}

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\item{\bf 4. Gravitational frequency shift.} 
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The following Fortran program returns a time difference of 
5.5 micro seconds due to the gravitational frequency shift.
\input gfs.tex

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