A cylinder with a base radius of 5 cm and a height of 8 cm divides its base into many equal sectors, which are then assembled into an approximate cuboid. How much does the surface area of this cuboid increase compared to the cylinder?
一个底面半径是5厘米，高是8厘米的圆柱体，把它的底面分成许多相等的扇形，切开后拼成一个近似的长方体．这个长方体的表面积比圆柱体增加了多少？
<gadget id="calculator">5 * 8 * 2</gadget>
<output>80</output>

<result>80</result>