A beam of light consisting of two wave length 650 nm and 520 nm, is used to obtain interference finger in a young's double slit experiment . What is the least distance from the central maximum ? Where the bright fringer due to both wavelength coincide ?

Question

$\begin{array}{1 1} 2600 \frac{D}{d} nm \\ 2400 \frac{D}{d} nm \\ 600 \frac{D}{d} nm \\ 2000 \frac{D}{d} nm \end{array} $