If the two sides of a triangle are 5cm and 7cm, the perimeter of this triangle cannot be how many centimeters.
一个三角形的两条边分别是5cm和7cm，这个三角形的周长不可能是多少厘米．
<gadget id="calculator">7 - 5</gadget>
<output>2</output>

<gadget id="calculator">2 + 7 + 5</gadget>
<output>14</output>

<result>14</result>