For Question B) we use Grahams Law. The law states (Rate 1/Rate2)=(M2/M1)^1/2. We plug in our known values into the formula and get: 1.81=(273.1/M1)^1/2. Square both sides to get 3.2761 = 273.1/M1. Multiply both sides by M1 and get M1 x 3.2761 = 273.1. Divide both sides by 3.2761 and get M1 = 273.1 / 3.2761. M1 = 83.36.