In Young's double slit experiment, the interference bright fringes are of:

In Young's double slit experiment interference fringes 1^(@) apart are produced on the screen, the slit separation is (lambda = 589 nm)

In Young’s double slit experiment, the central bright fringe can be identified

In Young’s double slit experiment, the central bright fringe can be identified

In a Young's double-slit experiment, the central bright fringe can be identified

In Young's double slit experiment the interference pattern is found to have an intensity ratio between bright and dark fringes as 9. This implies