(A) The pressure at 10 m below the surface of the ocean is about 2.00×10^5 Pa. Which of the following statements is true? a) The weight of a column of seawater 1 m^2 in cross-section and 10 m high is about 2.00×10^5 N. b) The weight of a column of seawater 1 m^2 in cross-section and 10 m high plus the weight of a column of air with the same cross-section extending up to the top of the atmosphere is about 2.00×10^5 N. c) The weight of 1 m3 of seawater at 10 m below the surface of the ocean is about 2.00×10^5 N. d) The density of seawater is about 2.00×10^5 times the density of air at sea level. (B) Now consider the pressure 20 below the surface of the ocean. Which of the following statements is true? a) The pressure is twice that at a depth of 10 m. b) The pressure is the same as that at a depth of 10 m. c) The pressure is equal to that at a depth of 10 m plus the weight per 1 m^2 cross-sectional area of a column of seawater 10 m high. d) The pressure is equal to the weight per 1 m^2 cross-sectional area of a column of seawater 20 m high.