Light is incident on a diffraction grating with 7200 slits / cm and the pattern is viewed on a screen located 2.5 m from the grating. The incident light beam consists of two wavelengths, λ1 = 4.4 x 10-7 m and λ2 = 6.8 x 10-7 m Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.