Every square meter of grass can release 15 grams of oxygen a day. How many grams of oxygen can a circular grass with a circumference of 94.2 meters release in a day?
每平方米草地一天能释放氧气15克．一块周长94.2米的圆形草地，一天能释放氧气多少克？
<gadget id="calculator">2 * 3.14</gadget>
<output>6.28</output>

<gadget id="calculator">94.2 / 6.28</gadget>
<output>15</output>

<gadget id="calculator">15 ** 2</gadget>
<output>225</output>

<gadget id="calculator">3.14 * 225 * 15</gadget>
<output>10_597.5</output>

<result>10_597.5</result>