2. Two of the stable isotopes of mercury are 198Hg and 202Hg. These isotopes emit slightly different wavelengths of light, 546.07532nm and 546.07355nm, respectively. To identify which isotopes are included in a sample of mercury, we can shine the light on a diffraction grating with a screen 4m away. How far apart are the first-order bright fringes on the screen if the diffraction grating has 4,000 lines per centimeter