9. The period of incomplete darkness when the upper limb of the sun is below the visible horizon, and the center of the sun is not more than 6° below the celestial horizon. It is:
(A) Civil twilight
(B) Nautical twilight
(C) Astronomical twilight
(D) Global Horizon twilight
詳解 (共 2 筆)
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(A) Civil twilight 民...
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當太陽上緣低於可見地平線，而太陽中心低於...
阿摩線上測驗
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