(一)
1/S = (1-0.2)/1 + (20%*60%)/1 +(20%*40%)/2.5(汙泥無機比重)
1/S = 0.8/1 + 0.12/1 +0.08/2.5
1/S = 0.8 + 0.12 +0.32
S = 1/0.952
S= 1.05 (污泥比重)