Young's double slit interference apparatus is immersed in a liquid of refractive index \( 1.44 \). It has slit separation of \( 1.5 \,\text{mm} \). The slits are illuminated by a parallel beam of light whose wavelength in air is \( 690 \,\text{nm} \). The fringe-width on a screen placed behind the plane of slits at a distance of \( 0.72 \,\text{m} \), will be:
