A company broadcasts a 30-second advertisement on the prime time of a TV station. Play it once a day for two consecutive weeks, and pay a total of 357,000 yuan. How much is the average cost per second to play this advertisement?
某公司在电视台黄金档播一则30秒的广告．每天播放一次，连续两周，共付人民币35.7万元，播放这则广告平均每秒多少元钱？
<gadget id="calculator">35.7 * 10_000</gadget>
<output>357_000</output>

<gadget id="calculator">30 * 7 * 2</gadget>
<output>420</output>

<gadget id="calculator">357_000 / 420</gadget>
<output>850</output>

<result>850</result>