Let the one-way distance be D km.<br><br>&bull; With tailwind (A to B): speed = 500 + 50 = 550 km/h, time = D/550.<br>&bull; With headwind (B to A): speed = 500 − 50 = 450 km/h, time = D/450.<br>&bull; Total time = 2 h.<br><br>D/550 + D/450 = 2<br>D × (1/550 + 1/450) = 2<br>D × ((450 + 550)/(550 × 450)) = 2<br>D × (1000/247500) = 2<br>D = 2 × 247500/1000 = 2 × 247.5 = 495 km.<br><br>Final Answer: 495 km