A piece of parallelogram land has a base of 400 meters and a height of 50 meters. It can harvest 4.2 tons of wheat per hectare. How many tons of wheat can this land harvest?
一块平行四边形土地，底是400米，高是50米，每公顷可收小麦4.2吨，这块地可收小麦多少吨？
<gadget id="calculator">50 / 10_000</gadget>
<output>1/200 = around 0.005</output>

<gadget id="calculator">4.2 * 400 * (1/200)</gadget>
<output>8.4</output>

<result>8.4</result>