A rectangular forest is 126 meters long and 72 meters wide. If each square meter can produce about 3 kilograms of oxygen per month, how many kilograms of oxygen can this forest produce per month?
一片长方形的树林长126米，宽72米，如果每平方米一月大约可生产氧气3千克，那么这片树林一个月大约可生产氧气多少千克？
<gadget id="calculator">126 * 72 * 3</gadget>
<output>27_216</output>

<result>27_216</result>