The diameter of the base of a cylinder is 3 decimeters, and its sides are expanded to form a square. What is the height of the cylinder?
一个圆柱底面直径是3分米，把它的侧面展开正好是一个正方形，这个圆柱的高是多少．
<gadget id="calculator">3.14 * 3</gadget>
<output>9.42</output>

<result>9.42</result>