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A spare buoy is a buoyant rod weighted to float and protrude vertically, as shown in the figure below. Suppose that the buoy is made of maple wood ( specific gravity, s=0.6 ), has a rectangular cross section (2.54 cm by 2.54 cm ), a length of 3.7 m, and is floating in seawater ( specific gravity, s=1.025 ). What weight of steel should be added to the bottom end of the buoy so that h=45 cm ? (The specific gravity of steel, s=7.85 ) (Answer: Wsteel ​=8.1 N ). (20 Points) (Fall 2015 - Midterm Exam)