Uncontrolled airspace is designated Class F, while controlled airspace below 5,490m above sea level and not in the vicinity of an airport is Class E.

无交通管制的空域被定为等级 F，而低于海拔5490米、不在机场附近的管制空域是等级 E。

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Moisture condensation is excluded, as the components are only permitted for humidity class f.

把湿度浓缩排除在外，因为配件仅允许湿度等级为f。

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Therefore, class F amplifier has caused widespread concern at home and abroad, and also has good prospects for the study.

所以F类放大器在国内外已经引起了广泛的关注，并拥有很好的研究前景。

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Mercedes-Benz has the A-Class E Cell, sold only in Europe, and the B-Class F-CELL, but plans to debut the SLS-AMG E Cell in a battery electric version by 2013.

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More than just megapixels, its best-in-class f-2.0 lens with a backside illuminated sensor takes amazing pictures in low light and its quick launch feature makes sure you never miss an important moment.

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Now the larger version, a new class we dubbed the F-class, has been specially configured for being able to carry very large and over-dimensional pieces, and has no line-of-sight issues.

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