Editors' Workloads Were Increasing During the 1990s, as the Following

Multiple Choice

Editors' workloads were increasing during the 1990s, as the following table shows. $\begin{array} { | l | l | l | l | l | } \hline & \mathbf { 1 9 9 3 } & \mathbf { 1 9 9 4 } & \mathbf { 1 9 9 5 } & \mathbf { 1 9 9 6 } \\\hline \text { Books/Editor } & 2.9 & 4 & 4.8 & 5.5 \\\hline \text { Editors } & 20,000 & 18,000 & 9,500 & 10,000 \\\hline\end{array}$ Which matrix expression would estimate the total number of books edited during the years 1993-1996

A) $\left[ \begin{array} { l l l l } 20,000 & 18,000 & 9,500 & 10,000\end{array} \right] \cdot \left[ \begin{array} { c } 2.9 \\4 \\4.8 \\5.5\end{array} \right]$
B) $\left[ \begin{array} { l l l l } 2.9 & 4 & 4.8 & 5.5\end{array} \right] \cdot \left[ \begin{array} { c } 20,000 \\18,000 \\9,500 \\10,000\end{array} \right]$
C) Both $\left[ \begin{array} { l l l l } 2.9 & 4 & 4.8 & 5.5\end{array} \right] \cdot \left[ \begin{array} { c } 20,000 \\18,000 \\9,500 \\10,000\end{array} \right]$ and $\left[ \begin{array} { l l l l } 20,000 & 18,000 & 9,500 & 10,000\end{array} \right] \cdot \left[ \begin{array} { c } 2.9 \\4 \\4.8 \\5.5\end{array} \right]$
D) Both $\left[ \begin{array} { l l l l } 2.9 & 4 & 4.8 & 5.5\end{array} \right] \cdot \left[ \begin{array} { c } 10,000 \\9,500 \\18,000 \\20,000\end{array} \right]$ and $\left[ \begin{array} { l l l l } 20,000 & 18,000 & 9,500 & 10,000\end{array} \right] \cdot \left[ \begin{array} { c } 5.5 \\4.8 \\4 \\2.9\end{array} \right]$
E) $\left[ \begin{array} { c } 20,000 \\18,000 \\9,500 \\10,000\end{array} \right] \cdot \left[ \begin{array} { l l l l } 2.9 & 4 & 4.8 & 5.5\end{array} \right]$