A cylindrical oil storage barrel has a bottom radius of 5dm and a height of 1m. After it is filled with oil, if the oil weighs 0.7kg per liter, how much does the barrel weigh?
一个圆柱形储油桶，底面半径是5dm，高1m，装满油之后，若每升油重0.7千克，这桶油重多少千克？
<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 1 * 10 * 0.7</gadget>
<output>549.5</output>

<result>549.5</result>