Statement 1: If the whole apparatus of Young's experiment is immersed in liquid, the fringe width will decrease.

Statement 2: The wavelength of light in water in more that of air.

When whole of the apparatus is immersed in water, then wavelength of light decreases form the relation ${\mathrm{\lambda }}^{\mathrm{\prime }}=\mathrm{\lambda }/\mathrm{\mu },\mathrm{\mu }$ being refractive index of water.

Therefore, fringe width $\left(\mathrm{\beta }=\frac{\mathrm{D\lambda }}{\mathrm{d}}\text{ or }\mathrm{\beta }\propto \mathrm{\lambda }\right)$ will decrease as $\lambda$ decreases when immersed in water. 

Also we conclude that wavelength of light in water is less than that in air.