Two identical horizontal sheets of glass have a thin film of air of thickness t between them. The glass has refractive index 1.40. The thickness t of the air layer can be varied. Light with wavelength A in air is at normal incidence onto the top of the air film. There is constructive interference between the light reflected at the top and bottom surfaces of the air film when its thickness is 680 nm. For the same wavelength of light the next larger thickness for which there is constructive interference is 952 nm. What is the wavelength A of the light when it is traveling in air? Express your answer to three significant figures and include the appropriate units. Value Units What is the smallest thickness t of the air film for which there is constructive interference for this wavelength of light? Express your answer to three significant figures and include the appropriate units. Value Units