(a) A dust particle with a diameter of 0.0012 in and a specific gravity of 3.6 falls in the air (standard atmosphere at sea level, \rho = 0.0023768 slugs/ft^{3} , \mu = 0.37372 \times 10^{-6} lb-sec/ft^{2} , \gamma = 0.076472 lb/ft^{3} ), as illustrated in Figure EP 10.8a, and settles to the ground after a windstorm. Determine the terminal (free-fall) velocity for the dust particle as it falls to the ground. (b) Mathematically illustrate how Stokes law is applied in the use of a falling sphere viscometer to determine the viscosity of a fluid.