PLEASE HELP ME WITH THESE TWO QUESTIONS AND PROVIDE ANSWER ONLY AS A DECIMAL

1. Light of wavelength 635 nm falls on a 0.48 mm wide slit and forms a diffraction pattern on a screen 1.6 m away.(a) Find the position of the first dark band on each side of the central maximum.

.....nm

2. (b) Find the width of the central maximum.

....... mm