\documentclass{beamer}
 \usetheme{CambridgeUS}
 \usecolortheme{rose}
\graphicspath{{./Fig/}}

 \begin{document}
\title{Test Slide using {\tt beamer} package}
\author{Test Test}
\date{}
\begin{frame}
\titlepage

\begin{center}
Department of Mathematics\\
Yazd University
\end{center}
\end{frame}
\begin{frame}[t]{Title}{Subtitle}
\begin{itemize}
\item one \pause
\item two \pause
\item three
\end{itemize}
$$L_k(p,q)=\min\left\{L_{k-1}(p,q), \min\limits_{{i+j=k}\choose{r\in V\setminus\{p,q\}}} \{L_{i}(p,r)+L_j(r,q) \} \right\}.$$
\end{frame}
\begin{frame}
Test Text
\begin{center}
\includegraphics<2-3>[height=6cm]{Art-Gallery-small}
\includegraphics<3-4>[height=6cm]{Plan-camera}
\includegraphics<5-6>[height=6cm]{Camera-visibility}
\end{center}

\only<2-3>{Test Text2}
\end{frame}
\begin{frame}
\begin{block}<3-5>{Theorem 1.2.3}
This is a sample text.
\begin{itemize}
\item one \pause
\item two \pause
\item three
\end{itemize}
\includegraphics<2-3>[height=4cm]{Art-Gallery-small}
\end{block}
\end{frame}
\begin{frame}{}
\centerline{\LARGE END.}
\end{frame}

\end{document}