Answer:
474.59 mg/L
Explanation:
Given that 
BOD = 30 mg/L
Original BOD  = 30 mg/L × dilution factor
Original BOD  = 30 mg/L  × 10 = 300 mg/L

here  is the ultimate BOD ; BOD is the  biochemical oxygen demand ;  t = 0.20 /day
 is the ultimate BOD ; BOD is the  biochemical oxygen demand ;  t = 0.20 /day

 
 
 
        
             
        
        
        
Answer:
t= 4.5 mm
Explanation:
Given that
P = 520 KPa ( gauge)
Maximum allowable normal stress ,σ= 150
d= 2.6 m
Wall thickness = t
The normal stress for pressure vessel given as 
 ( hoop stress)
               ( hoop stress)
We always take maximum stress for safe design.

Now by putting the values

t= 4.5 mm
So the minimum thickness, t, of the wall is 4.5 mm
 
        
             
        
        
        
Answer:
nothing much what class r u in