A forest park on the outskirts of a certain city has 180 hectares of forest, and 1 hectare of forest can hold about 30 tons of dust a year. About how many tons of dust can this park hold in a year?
某市郊外的森林公园有180公顷森林，1公顷森林一年可滞尘约30吨．这个公园一年大约可滞尘多少吨？
<gadget id="calculator">180 * 30</gadget>
<output>5_400</output>

<result>5_400</result>