In a young's double slit experiment, a student observes 8 fringes in a certain segment of screen when a monocromatic light of 600nm wavelength is used. If the wavelength of light is a changed to 400nm, then the number of fringes he would observe in the same region of the screen is:
(1) 9
(2) 12
(3) 6
(4) 8
(1) 9
(2) 12
(3) 6
(4) 8