應該根據自己的高度和下墜的速度吧。應該身上有儀器告訴你該開傘。如果自己決定，就要根據高度和速度計算

來源: 大財主於 2015-10-09 11:07:44 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

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