The shape of a cabbage field is trapezoid, its upper base is 40 decimeters, its lower base is 100 decimeters, and its height is 8 meters. If each cabbage covers an area of 8 square decimeters on average, how many cabbages can be planted in this land?
一块白菜地的形状是梯形，它的上底是40分米，下底是100分米，高是8米．如果平均每棵白菜占地8平方分米，这块地一共可种白菜多少棵？
<gadget id="calculator">40 + 100</gadget>
<output>140</output>

<gadget id="calculator">8 * 10</gadget>
<output>80</output>

<gadget id="calculator">80 / 2 / 8</gadget>
<output>5</output>

<gadget id="calculator">140 * 5</gadget>
<output>700</output>

<result>700</result>