To dig a cylindrical cistern with a bottom circumference of 6.28 meters, and to make the cistern able to store 78.50 liters of water, how many meters deep should the cistern be dug?
要挖一个底面周长是6.28米的圆柱形蓄水池，要使蓄水池能蓄水78.50升，这个蓄水池要挖多少米深？
<gadget id="calculator">6.28 / 3.14 / 2</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<gadget id="calculator">78.5 / 1_000 / 3.14</gadget>
<output>0.025</output>

<result>0.025</result>