How does the fringe of interference fringes change, when the whole apparatus Young's experiment is kept in water (refract index 4/3)?

How does the fringe width of interference fringes change, when the whole apparatus of Young's experiment is kept in a liquid of refractive index 1.3 ?

How does the fringe width of interference fringes change, when the whole apparatus of Young's experiment is kept in a liquid of refractive index 1.3 ?

How does the fringe width of interfernce fringe change, when the whole apparatus of Young's experiment is kept in a liquid of refractive index 1.3?

How does the angular separation of interference fringes change in Young's experiment, if the distance between slits is increased .

In a Young's double slit experiment, the fringe width is found to be 0.4mm . If the whole apparatus is immersed in water of refractive index 4//3 without disturbing the geometrical arrangement, the new fringe width will be