Have you learnt everything, ...a lot, ...something? Do you understand the topic?

- Can you distinguish between when light behaves like a particle and when it behaves like a wave?    
- Do you know what reflection is and how a ray of light behaves when it hits a flat mirror and a convex one?
- Do you know the phenomenon of refraction and how a ray of light behaves when it passes through a converging lens and a diverging one?
- Do you understand the basics of a telescope and what you should look for if you went to buy one? 
- Do you know how a photoelectric cell works and what consequences can be drawn from the experiment that you have simulated? This interpretation explains what cannot be explained using the electromagnetic theory of light.