I have my physics exam tomorrow please tell me important topic for ray optics i have not done that

I have my physics exam tomorrow please tell me important topic for ray

1.	I have my physics exam tomorrow please tell me important topic for ray optics i have not done that
Answer» •Lens Maker formula•Total intarnal reflection•Compound macroscope and astronomical macroscope•Numericals on lens combination•Prism and dispersion This will be enough...