There is a square vegetable field with a side length of 15 meters, and 30 kilograms of cabbage can be harvested per square meter. How many kilograms of cabbage can be harvested in total?
有一块正方形菜地，边长是15米，每平方米可收获30千克白菜．一共可收获多少千克白菜？
<gadget id="calculator">15 * 15 * 30</gadget>
<output>6_750</output>

<result>6_750</result>