If the perimeter of a rectangle is 30 cm and its length and width are prime numbers, what is its area in square centimeters?
一个长方形周长是30厘米，长和宽都是质数，则它的面积是多少平方厘米．
<gadget id="calculator">13 * 2</gadget>
<output>26</output>

<result>26</result>