A Firm of Four Departments Has the Following Trip Matrix

A firm of four departments has the following trip matrix and current block plan of all departments: $$\begin{array} { | l | c | c | c | c | } \hline \begin{array} { c } \text { Dept. } \\\text { Name }\end{array} & \text { A } & \text { B } & \text { C } & \text { D } \\\hline \mathrm { A } & - & 14 & 6 & 9 \\\hline \text { B } & & - & 7 & 16 \\\hline \text { C } & & & & 2 \\\hline \text { D } & & & & - \\\hline\end{array}$$ $$\begin{array} { | l | l | } \hline A & B \\\hline D & C \\\hline\end{array}$$ a. What is the load- distance score for the current layout? (Assume rectilinear distance and that the distance between departments A and B is one unit of distance.)
b. What would be the load- distance score for the following layout? $$\begin{array} { | c | c | } \hline \text { A } & \text { C } \\\hline \text { D } & \text { B } \\\hline\end{array}$$