A cuboid has a length of 7 decimeters, a width of 4 decimeters, and a height of 2 decimeters. What is the surface area in square decimeters?
一个长方体，长7分米，宽4分米，高2分米，表面积是多少平方分米．
<gadget id="calculator">7 * 4</gadget>
<output>28</output>

<gadget id="calculator">7 * 2</gadget>
<output>14</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">28 + 14 + 8</gadget>
<output>50</output>

<gadget id="calculator">50 * 2</gadget>
<output>100</output>

<result>100</result>