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2008 年北京奧運會主體育場的外形好似“鳥巢” ( The Bird Nest ）。有一類硼烷也好似鳥巢，故稱為巢式硼烷。巢式硼烷除 B₁₀H₁₄不與水反應外，其余均易與水反應生成氫氣和硼酸，硼烷易被氧化。下圖是三種巢式硼烷，有關說法正確的是

A．這類巢式硼烷的通式是 C _nH _{n + 4}

B．2B₅H₉ + 12O₂5B₂O₃ 十9H₂O ，l molB₅H₉完全燃燒轉移25mol電子

C．8 個硼原子的巢式棚烷化學式應為 B₈H₁₀

D．硼烷與水反應是非氧化還原反應

All the dishes in this menu, ______ otherwise stated, will serve two to three people.

A. as         B. if        C. though       D. unless

All the dishes in this menu, ______ otherwise stated, will serve two to three people.

A. as         B. if        C. though       D. unless

All the dishes in this menu, ______ otherwise stated, will serve two to three people.

A. as         B. if        C. though       D. unless

All the dishes in this menu, ______ otherwise stated, will serve two to three people.

A. as         B. if        C. though       D. unless