Find the length or surface area of a cube: the length is 24 decimeters, the width is 13 centimeters, and the height is 15 centimeters.
求长或正方体的表面积：长是24分米，宽是13厘米，高是15厘米．
<gadget id="calculator">24 * 10</gadget>
<output>240</output>

<gadget id="calculator">240 * 13</gadget>
<output>3_120</output>

<gadget id="calculator">240 * 15</gadget>
<output>3_600</output>

<gadget id="calculator">13 * 15</gadget>
<output>195</output>

<gadget id="calculator">3_120 + 3_600 + 195</gadget>
<output>6_915</output>

<gadget id="calculator">6_915 * 2</gadget>
<output>13_830</output>

<result>13_830</result>