A large square is formed by 9 squares with a side length of 2 cm. What is the perimeter of this large square in cm?
用9个边长2厘米的正方形围成一个大正方形，这个大正方形的周长是多少厘米？
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<result>24</result>