There is a trapezoidal vegetable field, the upper base is 42 meters, the lower base is 58 meters, and the height is 40 meters. If 25 kilograms of cabbage is harvested per square meter, how many kilograms of cabbage are harvested in this land?
有一块梯形的菜地，上底是42米，下底是58米，高是40米．如果每平方米收25千克白菜，这块地一共收白菜多少千克？
<gadget id="calculator">42 + 58</gadget>
<output>100</output>

<gadget id="calculator">40 / 2</gadget>
<output>20</output>

<gadget id="calculator">100 * 20 * 25</gadget>
<output>50_000</output>

<result>50_000</result>