The height of a cylinder is 10 cm, and its sides are expanded to obtain a square. What is the lateral area of this cylinder in square centimetres.
一个圆柱的高是10厘米，把它的侧面展开，得到一个正方形．这个圆柱体的侧面积是多少平方厘米．
<gadget id="calculator">10 * 10</gadget>
<output>100</output>

<result>100</result>