To put a wire hoop on the outside of a cylindrical bucket with a bottom radius of 12 cm, and the joint part is 8 cm, how many centimeters of wire is needed?
要在底面半径是12厘米的圆柱形水桶外面打上一个铁丝箍，接头部分是8厘米，需用铁丝多少厘米．
<gadget id="calculator">3.14 * 12 * 2</gadget>
<output>75.36</output>

<gadget id="calculator">75.36 + 8</gadget>
<output>83.36</output>

<result>83.36</result>