Use plastic to pave a circular field with a diameter of 24 meters. If the plastic costs 350 yuan per square meter, how much does it cost to pave this circular field?
用塑胶铺一个直径是24米的圆形场地，如果每平方米塑胶需要350元，铺这个圆形场地需要多少钱？
<gadget id="calculator">24 / 2</gadget>
<output>12</output>

<gadget id="calculator">12 ** 2</gadget>
<output>144</output>

<gadget id="calculator">144 * 3.14 * 350</gadget>
<output>158_256</output>

<result>158_256</result>