A piece of rectangular paper is 40 cm long and 8 cm wide. Fold it in half and then in half again. After opening, it forms the sides of a cuboid with a height of 8 cm. If you want to assign a base to this cuboid, what is the area in square centimetres?
一张长方形纸长40厘米，宽8厘米，把它对折、再对折．打开后，围成一个高8厘米的长方体的侧面．如果要为这个长方体配一个底面，面积是多少平方厘米
<gadget id="calculator">40 / 4</gadget>
<output>10</output>

<gadget id="calculator">10 * 10</gadget>
<output>100</output>

<result>100</result>