How many excess electrons must be distributed uniformly within the volume of an isolated plastic sphere 28.0 cmcm in diameter to produce an electric field of 1050 N/CN/C just outside the surface of the sphere?

Two lasers are shining on a double slit, with slit separation d. laser 1 has a wavelength of d/20, whereas laser 2 has a wavelength of d/15. the lasers produce separate interference patterns on a screen a distance 5.30 m away from the slits. part a which laser has its first maximum closer to the central maximum? view available hint(s) which laser has its first maximum closer to the central maximum? laser 1 laser 2