If the length of a rectangle is 3.2 cm and the width is 2.1 cm, what is its area in square centimeters?
一个长方形的长是3.2厘米，宽是2.1厘米，它的面积是多少平方厘米．
<gadget id="calculator">3.2 * 2.1</gadget>
<output>6.72</output>

<result>6.72</result>