A student holds a laser which emits light of wavelength 633nm. The beam passes via a pair of slits separated through 0.300mm, in a glass plate joined to the front of the laser. The beam then falls perpendicularly on the screen, making an interference pattern on it. The student starts to walk directly toward the screen at 3.00m/s. The central maximum on the screen is stationary. Determine the speed of the first-order maxima on the screen.