A cylindrical chimney is made from a piece of iron sheet with a length of 2.5 meters and a width of 1.5 meters. What is the lateral area of the chimney? (neglected at the interface)
用一张长2.5米，宽1.5米的铁皮做一个圆柱形烟筒，这个烟筒的侧面积是多少？(接口处忽略不计)
<gadget id="calculator">2.5 * 1.5</gadget>
<output>3.75</output>

<result>3.75</result>