The two adjacent sides of a rectangle are 3cm and 4cm respectively. Taking the 3cm side as the axis, a cylinder is obtained by rotating it once. What is the lateral area of this cylinder in cm**2.
一个长方形相邻的两条边分别为3cm，4cm，以3cm的边为轴，旋转一周就得到了一个圆柱，这个圆柱的侧面积是多少cm**2．
<gadget id="calculator">3.14 * 4 * 2 * 3</gadget>
<output>75.36</output>

<result>75.36</result>