Mr. Gan Qiangsheng plans to open up a parallelogram vegetable field in his own open space. The bottom is 12 meters, and the height is 4 meters. This vegetable field has an average of 3 cabbages per square meter. How many classes can be planted in this vegetable field? Chinese cabbage?
干强胜老师准备在自家的空地开辟一块平行四边形的菜地，底是12米，比高长4米，这块菜地平均每平方米种3棵白菜，这块菜地一共可以种植多少课白菜？
<gadget id="calculator">12 - 4</gadget>
<output>8</output>

<gadget id="calculator">12 * 8</gadget>
<output>96</output>

<gadget id="calculator">96 * 3</gadget>
<output>288</output>

<result>288</result>