光学显微镜的放大倍数受限于可见光的波长，大约500纳米。

The power of a light microscope is limited by the wavelength of visible light, which is about 500 nm.

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HTC的主要对手，诺基亚、三星和苹果，销售了大约其两倍数量的智能手机。

HTC's main rivals, Nokia, Samsung and Apple, still sell around twice as many smartphones.

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当那是时，以前大约从一年加倍数字， 它仅仅是很少的400 百万加世界范围的因特网用户。

While that's about double the number from the year before, it's only a fraction of the 400 million-plus Internet users worldwide.

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