Monochromatic light with a wavelength of 6.4 E -7 meter passes through two narrow slits, producing an interference pattern on a screen 4.0 meters away. The first order bright band lines are 2.0 E -2 m

Monochromatic light with a wavelength of 6.4 E -7 meter passes through two narrow slits, producing an interference pattern on a screen 4.0 meters away. The first order bright band lines are 2.0 E -2 meters away from the central bright maxima. What is the distance between the slits?

1.3 E -4 m

8.0 E -6 m

3.2 E -9 m

7.8 E3 m