If the Young's double slit experiment is performed with white light,then which of the following is not true?

If the slit widths of $YDSE$ are in the ratio $1:4$,then the ratio of maximum to minimum intensity on the screen is: (in $:1$)

In a Young's double slit experiment,the wavelength of red light is $7.8 \times 10^{-5} \,cm$ and that of blue light is $5.2 \times 10^{-5} \,cm$. The value of $n$ for which $(n+1)^{\text{th}}$ blue bright band coincides with $n^{\text{th}}$ bright red band is ..........

In Young's double slit experiment,the slits are $0.5 \, mm$ apart and the interference is observed on a screen at a distance of $100 \, cm$ from the slits. It is found that the $9^{th}$ bright fringe is at a distance of $7.5 \, mm$ from the $2^{nd}$ dark fringe on the same side of the central fringe. The wavelength of the light used is ..... $\mathring{A}$.

Imagine a Young's double-slit interference experiment performed with waves associated with fast-moving electrons produced from an electron gun. The distance between successive maxima (fringe width) will decrease if:

In Young's double-slit experiment,if the distance between the slits is reduced to half and the distance between the slit and the screen is doubled,then the fringe width