Some homework q's i don't quite understand. Any help is appreciated. A double slit arrangement produces fringes on a distant screen. Using the light from a sodium spectral lamp (lamda = 589 nm) the fringes have an angular separation of 0.015 degrees. a) What is the separation of the slits? b) What would the new angular separation be if i) the slit separation were doubled? ii) the distance to the screen were doubled? iii) the entire arrangement were immersed in water (n=1.33)? iv) the sodium lamp were replaced by an argon ion laser (lamda = 488 nm)?