There is a conical steel material with a base radius of 4 cm and a height of 0.3 m. It is to be melted and cast into a rectangular parallelepiped steel with a cross-sectional area of 4 square centimeters. What is the length of the rectangular parallelepiped in centimeters?
有一个圆锥形钢材，底面半径4厘米，高0.3米，要把它熔铸成横截面积是4平方厘米的长方体钢材，这个长方体的长是多少厘米？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">0.3 * 100</gadget>
<output>30</output>

<gadget id="calculator">30 / 4</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">(1/3) * 3.14 * 4 * 4 * (15/2)</gadget>
<output>125.6</output>

<result>125.6</result>