A certain reagent is added to a suspension of cells 4 μm in diameter. These cells have a density of 1.08 g/cm³, and they are suspended in liquid with a density of 1.00 g/cm³ and viscosity of 1.00 cP. This reagent causes the cells to form solid aggregates, all of which are 90 um in a diameter and have density of 1.04 g/cm³
Assuming that most of the sediment are formed at the top. How much time is required for all the aggregates to sediment to within 1 cm of the 50 cm high vessel filled with the suspension?