A cube cardboard box with a side length of 30 cm is placed in the corner, what is the exposed surface area?
一个棱长是30厘米的正方体纸箱放在墙角，露在外面的面的面积是多少．
<gadget id="calculator">30 * 30 * 3</gadget>
<output>2_700</output>

<result>2_700</result>