The store asked Xiong's advertising company to make a trapezoidal billboard, with the upper bottom 4 meters long, the lower bottom 6 meters long, and the height 2 meters. If the billboard charges 30 yuan per square meter, how much should the store pay?
商店请熊氏广告公司做了一块梯形广告牌，上底长4米，下底长6米，高2米．如果广告牌每平方米收费30元，那么商店该付多少钱？
<gadget id="calculator">4 + 6</gadget>
<output>10</output>

<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">10 * 1 * 30</gadget>
<output>300</output>

<result>300</result>