6. In a shallow pool of water there are two needle-like dippers that move up and down at the same constant frequency. The water waves move outward from each source as shown in the drawing. The wave crests, represented by solid lines, have amplitude 3 cm. What is the displacement of the water (relative to the undisturbed level) at point P? a) - 3 cm b) 0 cm c) + 3 cm d) + 6 cm

6. In a shallow pool of water there are two needle-like dippers that move up and down at the same constant frequency. The water waves move outward from each source as shown in the drawing. The wave crests, represented by solid lines, have amplitude 3 cm. What is the displacement of the water (relative to the undisturbed level) at point P? a) - 3 cm b) 0 cm c) + 3 cm d) + 6 cm