In a Young's Double-Slit Experiment, a Thin Sheet of Mica

Multiple Choice

In a Young's double-slit experiment, a thin sheet of mica is placed over one of the two slits.As a result, the center of the fringe pattern (on the screen) shifts so that the center is now occupied by what was the 30^th dark band.The wavelength of the light in this experiment is 480 nm and the index of the mica is 1.60.The mica thickness is:

A) 0.009 mm
B) 0.012 mm
C) 0.014 mm
D) 0.024 mm
E) 0.062 mm