A cuboid copper is 2m long and has a cross-sectional area of 25cm**2. It is known that every dm**3 of copper weighs 8.9kg, how many kilograms does this piece of copper weigh?
一根长方体铜材长2m，横截面面积是25cm**2，．已知每dm**3铜重8.9kg，这根铜材重多少千克？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">(1/4) * 20 * 8.9</gadget>
<output>44.5</output>

<result>44.5</result>