Can anyone please help me out with this physics problem please I just need a real answer please!

Light from a sodium lamp passes through a diffraction grating that has 1000 slits per millimeter. the interference pattern is viewed on a screen 1.000 m behind the grating. the first (m = 1) two bright yellow fringes that are visible are 0.7288 m and 0.7300 m from the central maximum. what are the wavelengths of these two fringes?

What is a subatomic particle with a negative charge and very little mass?

I’ve been stuck on this for a while