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 4.50 meter away from the slits.
a) Find which laser has its first maximum closer to the central maximum?
b) Find the distance between the first maxima (on the same side of the central maximum) of the two patterns?
c) What is the distance between the second maximum of laser 1 and the third minimum of laser 2, on the similar side of the central maximum? Express your answer in meters.