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A bathysphere used for deep sea explorations has a radius of 1.50m and a m of 1.20*10^4kg. In order to dive , this submarine takes on m in the form of sea water. Determine the m the submarine must take on so that can descend at a constant speed of 1.20m/s, when the upward resistive force on it is 1100N upward. The density of sea water is 1.03*10^3 kg/m^3.