A parallelogram-shaped vegetable field has an area of 0.21 hectares, its base is 70 meters, and its height is how many meters?
一块平行四边形的菜地，面积是0.21公顷，它的底是70米，高是多少米？
<gadget id="calculator">0.21 * 10_000</gadget>
<output>2_100</output>

<gadget id="calculator">2_100 / 70</gadget>
<output>30</output>

<result>30</result>