If the side of a cylinder is unfolded, it becomes a rectangle with a length of 5 cm and a width of 3 cm. What is the lateral area of the cylinder in cm**2.
一个圆柱的侧面展开后是一个长5cm，宽3cm的长方形，这个圆柱的侧面积是多少cm**2．
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>