試題詳解

2.A layer of oil with density 800 kg/m ³ floats on top of a volume of water with density 1,000 kg/m ³ . A block floats at the oil-water interface with 1/4 of its volume in oil and 3/4 of its volume in water, as shown in the figure below. What is the density of the block ? 
(A) 200 kg/m³
(B) 850 kg/m³
(C) 950 kg/m³
(D) 1,050 kg/m³
(E) 1,800 kg/m³