A piece of iron wire can form a rectangle with a length of 8 cm and a width of 2 cm. What is the length of the wire in cm?
一根铁丝可以围成一个长8厘米，宽2厘米的长方形，这根铁丝长多少厘米．
<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<result>20</result>