i think some of the answers given by u r wrong like c6de b q89 answer shud be 3,q70 it shud be 2 and sir in paragrah 75-77 it is not given in q abt how the rays r incident in the surface
i think some of the answers given by u r wrong like c6de b q89 answer shud be 3,q70 it shud be 2 and sir in paragrah 75-77 it is not given in q abt how the rays r incident in the surface