The following table gives the refractive indices of a few media:

              1          2                 3             4        5

Medium: water   Crown glass   Rock salt  Ruby   Diamond

Refractive index: 1.33  1.52   1.54   1.71   2.42

Use this table to give an example of :

(i) a medium pair so that light speeds up when it goes from one of these medium to another.

(ii) a medium pair so that light slows down when it goes from one of these medium to another.