1.For a temperature of 10 degree C, calculate the time needed for the following particles to settle 0.3m:
a) a 20um mineral particle with a specific gravity of 2.1, and
b) a 2 um organic particle with a specific gravity of 1.2
2.Assume that the current cost for a 120-pupil school constructed of wood frame for a city is $1,800,000. We are asked to develop an order-of-magnitude estimate for a 90-pupil school ?