Answer:a)It remains the same.
b)It decreases
Explanation:◇y = (wavelength×Length)/ distance
The wavelength of light is constant.
d = distance between the two slit. The value of d does not change so the fringes as well will not change.
b) As the space between the two slit becomes wider,the diffraction of light waves will become wider too.
When the width of the two slits are doubled,the diffraction of light forms larger angles and the intensive of the bright fringes decreases.