Complex sentence: The inward direction of the arrows at top and bottom indicates that where the Moon is 90 degrees away from overhead, its effect is perpendicular and does not change the strength of the Earth's attraction on the ocean.
Split into simpler sentences: The inward direction of the arrows at top and bottom indicates that where the Moon is 90 degrees away from overhead. Its effect is perpendicual and does not change the strength of the Earth's attraction on the ocean.