A triangular rice field has a base of 28 meters and a height of 30 meters. If it can produce 1.3 kilograms of rice per square meter, how many kilograms of rice can this rice field produce in total?
一块三角形稻田，底是28米，高是30米，如果每平方米可产大米1.3千克，这块稻田一共可产大米多少千克？
<gadget id="calculator">30 / 2</gadget>
<output>15</output>

<gadget id="calculator">28 * 15</gadget>
<output>420</output>

<gadget id="calculator">1.3 * 420</gadget>
<output>546</output>

<result>546</result>