<exercise>
<statement>
<p>Of the following three matrices, only two may be multiplied.
<me>
A=<xsl:value-of select="A"/> \hspace{1em} B=<xsl:value-of select="B"/> \hspace{1em} C=<xsl:value-of select="C"/>
</me>
Explain which two can be multiplied and why. Then show how to find their product.</p>
</statement>
<answer>
<me><xsl:value-of select="productName"/>=<xsl:value-of select="product"/></me>
</answer>
</exercise>