Q8. Hi please help with each question in photo. Will give thumbs up thanks!

An astronomer is calibrating a spectrometer that uses a diffraction grating to separate light in order of increasing wavelength (A, AB, and )c). She observes three distinct first-order spectral lines at the following respective angles 0m (where m denotes order). 0, = 12.60, 0, = 14.10, 0, = 15.30 (a) If the grating has 3,740 grooves per centimeter, what wavelength (in nm) describes each of these spectral lines? at 0, = 12.60 nm at 0, = 14.10 nm at 0, = 15.30 nm (b) At what angle (in degrees) would each of these lines be found in the second-order spectrum? for 2 A 0, = for A B 0 2 for * C Suppose Young's experiment is carried out in air, and then, in a second experiment, the apparatus is immersed in water. In what way does the distance between bright fringes change? O They move further apart. They move closer together. There is no change