A transparent coating of index 1.25 is deposited on glass of index 1.52 and observed in air at normal incidence. The coating is designed so that reflected light of wavelength 450 nm in air is bright (constructive) while reflected light of wavelength 600 nm in air is dark (destructive). Which coating thickness satisfies both requirements?
(a) 180nm
(b) 240nm
(c) 360nm
(d) 225nm