Hydrostatic pressure depends on density and depth Steps: - Pressure formula: P = ρ g h (ρ = density, g = acceleration due to gravity, h = depth). - For Liquid R: ρ_R g x = 4 kPa, so ρ_R g = 4 / x. - For Liquid Q: ρ_Q = 2 ρ_R, so ρ_Q g = 2 (4 / x) = 8 / x; set P = 7 kPa, so (8 / x) h = 7. - Solve for h: h = 7 (x / 8) = (7x)/8. Why B is correct: - Option B gives h = (7x)/8, matching the formula P = ρ g h after substituting densities and solving the proportion 2 h / x = 7 / 4. Why the others are wrong: - A: Assumes inverted pressure ratio (4/7) times half density ratio, ignoring correct proportion. - C: Applies density ratio to pressure ratio wrongly as h / x = (7/4) × 2 = 8/7. - D: Calculates depth for same 4 kPa pressure in Q, where h = x / 2. Final answer: …