A. 利用强力照明设备 B. 水面撒轻物 C. 投小石击起浪花 D. 以上均是
A. longitudinally framed B. transversely framed C. cellular framed D. web framed
A. any deck below the main deck and above the lowest deck B. a member that gives fore-and-aft strength C. made by placing two bulkheads a few feet apart D. a heavy fore-and-aft beam under the deck
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