Electromagnetic radiation question

As part of a laser light show, the technician is adjusting a diffraction grating. A green laser with a wavelength of 532 nm is shone on a diffraction grating with 2700 lines/cm. The screen is 35 m from the diffraction grating.

 a)  What is the distance between the slits of the diffraction grating?
  
 b)  How far from the central maximum will the bright fringe be?



A scientist is double-checking the wavelength of a new laser. The scientist sets up a diffraction grating with 5.00×10–6 m between slits, in front of the laser 1.50 m in front of a screen. The scientist measures the distance from the central maximum to the second bright fringe, which is 0.330 m. What is the wavelength of the laser?