This question is about visible light.
State one change that happens to light when it travels from water into air.
Diagram in Fig. 22.1 shows a ray of light from a starfish at the bottom of an aquarium filled with water.

Complete the ray diagram in Fig. 22.1 to show the path of the ray after it leaves the water. Include a normal line in your diagram.
Diagram in Fig. 22.2 shows three parallel incident rays hitting the textured surface of the starfish. Light is scattered from this surface.

Complete the diagram in Fig. 22.2 to show the scattered rays.
The starfish appears blue under white light.
Explain why the starfish appears black under red light.