A triangular spinach field has a base of 45 meters and a height of 28 meters. If you can harvest 3 kilograms of spinach per square meter. How many kilograms of spinach can be harvested from this field?
一块三角形菠菜地，底是45米，高28米．如果每平方米可以收获菠菜3千克．这块地一共可以收获菠菜多少千克？
<gadget id="calculator">28 / 2</gadget>
<output>14</output>

<gadget id="calculator">45 * 14</gadget>
<output>630</output>

<gadget id="calculator">3 * 630</gadget>
<output>1_890</output>

<result>1_890</result>