For a disc-shaped particle of diameter 2.55 mm and length 1 mm, calculate the following diameters: a) the equivalent volume sphere diameter; b) the equivalent surface sphere diameter; c) the surface-volume diameter (diameter of a sphere having the same external surface to volume ratio as the particle); d) the sieve diameter (width of the minimum aperture through which the particle will pass); e) the projected area diameters (diameter of a circle having the same area as the projected area of the particle resting in a stable position).