What is the effect on the fringe width of interference fringes in a Young's double slit experiment due to each of the following operations.
(a) The screen is moved away from the plane of the slits.
(b) The (monochromatic) source is replaced by another (monochromatic) source of shorter wavelength.
(c) The separation between the two slits is increased
(d) The width of two slits are slightly increased
(In each operation, take all parameters, other than the one specified to remain unchanged)