A cylinder is a square after its side is unfolded. It is known that the diameter of the base of the cylinder is 3 cm. What is the height of the cylinder in cm?
一个圆柱侧面展开后是一个正方形，已知这个圆柱的底面直径是3厘米，那么这个圆柱形的高是多少厘米．
<gadget id="calculator">3.14 * 3</gadget>
<output>9.42</output>

<result>9.42</result>