Last year, Weiliang Tungsten Co., Ltd. saved an average of 20 kilowatt-hours of electricity per month. According to this calculation, how much electricity was saved in a year.
伟良钨业公司去年平均每月节约用电20度，照这样计算，一年共节约用电多少度．
<gadget id="calculator">20 * 12</gadget>
<output>240</output>

<result>240</result>