Monochromatic green light of wavelength 550 nm illuminates two parallel narrow slits `7.7mu m` apart. The angular deviation `theta` of third order (for m =3) bright fringe in radian and in degree
A. `21.6, 12.4^(@)`
B. `0.216, 1.24^(@)`
C. `0.216, 12.4^(@)`
D. `216, 1.24^(@)`
