Calculate the sedimentation coefficient in water for (a) A spherical cell of 3 µm radius. (b) A spherical (or globular) macromolecule of 3 nm radius. Assume that the density of each is 1.05 g/cm3. (c) Calculate the number of g’s required in a centrifuge if the cells are to be sedimented through 2 cm in 5 min. (d) Similarly, calculate the number of g’s required to sediment the macromolecule at a rate of 1 mm/h