The added dose from cosmic rays during a coast-to-coast round trip flight in a commercial airplane is about 0.03 mSv.

在往返美国东西的一轮商业飞机飞行旅程中多受到0.03毫希来自宇宙射线时剂量。

youdao

If you have an airline miles rewards card, as I do (Southwest Visa), you can earn yourself a free round trip flight for about $20,000 in purchases.

如果你有一张航空积分里程信用卡，正如我说的（西南签证），你可以为你自己赢得一个价值20000美元的免费往返旅行班机。

youdao

If you have an airline miles rewards card, as I do (Southwest Visa), you can earn yourself a free round trip flight for about $20, 000 in purchases.

如果你有一张航空积分里程信用卡，正如我说的（西南签证），你可以为你自己赢得一个价值20000美元的免费往返旅行班机。

youdao

The price of a domestic round-trip flight has climbed more than 11 percent since 2009, when adjusted for inflation, according to the Bureau of Transportation Statistics.

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For its part, Eos appears to be overhauling its sales effort. (The company denies this.) One quirky promotion promises a free Apple video iPod for purchasing a round-trip flight by August 31.

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Two round-trip flights during the promotion will get you a free one-way flight, originating from Atlanta.

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