Cl If we wanted to get the chlorine, we could just put the chlorine over here, and we'd measure another radius there.

如果是，把Cl放这里，我们就可以测量另一个半径。

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Insect eyes differ fundamentally from animal eyes: the fly focuses light over a large radius through hundreds of separate facets, while animals focus it over a smaller radius through a single lens.

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It offers 56 megabits per second over a 30-mile radius. (The current standard is 11 megabits per second over a half-mile.) Wi-Max antennas on roofs and water towers will spring up like crazy and may begin to threaten the cable and local telephone empires.

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But an eight-inch wafer has a surface area of over 50 square inches (A four-inch radius squared times Pi).

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