rectangular broad-leaved forest is 40 meters long and 15 meters wide. Each square meter of broad-leaved forest can release about 2 kilograms of oxygen per month. How many kilograms of oxygen can this broad-leaved forest release per month?
一片长方形阔叶林，长40米，宽15米，每平方米阔叶林每月大约能放出2千克氧气，这片阔叶林每月大约能放出多少千克氧气？
<gadget id="calculator">40 * 15 * 2</gadget>
<output>1_200</output>

<result>1_200</result>