If the adjacent sides of a rectangle are 4 cm and 3 cm long, what is its perimeter?
一个长方形的邻边的长度分别是4厘米和3厘米，它的周长是多少．
<gadget id="calculator">4 + 3</gadget>
<output>7</output>

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

<result>14</result>