Solution:
Water has a refractive index of 1.33.
Air has a refractive index of 1.0003.
Glass has a refractive index of 1.5.
This shows that
μa < μw < μg
When light travels from a rarer to a denser medium, its speed drops, and it increases when it travels from a denser to a rarer media.
As a result, when a light ray crosses from water to air, the speed of light increases, and when the light ray passes from water to glass, the speed of light drops.