If recycling 1 ton of waste paper can produce 800 kilograms of paper, then how many kilograms of paper can the school recycle 4 tons of waste paper each year?
如果回收1吨废纸能再生产800千克纸，那么学校每年回收废纸4吨，共可再生产多少千克纸？
<gadget id="calculator">4 / 1</gadget>
<output>4</output>

<gadget id="calculator">800 * 4</gadget>
<output>3_200</output>

<result>3_200</result>