What Is the Optimal Location for These Departments in the Floor

What is the optimal location for these departments in the floor plan depicted if the transportation cost is $2 per foot and the departments have a daily number of trips between each other as shown?
Daily Number of Trips Between Departments
$$\begin{array} { | c | c | c | c | c | c | } \hline & \mathrm { A } & \mathrm { B } & \mathrm { C } & \mathrm { D } & \mathrm { E } \\\hline \mathrm { A } & \cdots & 20 & 40 & 60 & 80 \\\hline \mathrm { B } & & \cdots & 10 & 30 & 50 \\\hline \text { C } & & & \cdots & 0 & 15 \\\hline \mathrm { D } & & & & \cdots & 5 \\\hline \text { E } & & & & & \cdots \\\hline\end{array}$$ Floor Plan
$$\begin{array} { l | l | l | l | l } \hline \text { Office Space } 1 & \text { Office Space } 2 & \text { Office Space } 3 & \text { Office Space } 4 & \text { Office Space } 5 \\\hline\end{array}$$ Distance Between Offices
$$\begin{array} { | l | c | c | c | c | c | } \hline \text { Office Space } & 1 & 2 & 3 & 4 & 5 \\\hline \hline 1& \cdots & 10 & 20 & 30 & 40 \\\hline \hline2 & & \cdots & 10 & 20 & 30 \\\hline \hline 3& & & \cdots & 10 & 20 \\\hline \hline 4& & & & \cdots & 5 \\\hline 5 & & & & & \cdots \\\hline\end{array}$$