Question 508976
8 piles

16 inch diameter
8 feet deep
 in metric


First convert inch & foot to meters

1 inch = 2.54 cm 
2.54/100 = 0.02 meter  ( 100 cm = 1meter)

16 inch = 16*0.02 = 0.32 meter 

Diameter = 0.32meter ,  radius is half of that
=0.16 meter

Depth = 8 feet => 12*8 = 96 inches =>  96*0.02= 1.92 m

Volume of cylinder = pi*r^2*h    ( h= d in this case) r is radius of pile

V= 3.14 * (0.16)^2*1.92
V= 0.154 m^3 

This is for 1 pile
so for 8 piles it will be 8*0.154 = 1.23 m^3

Cheers!
Hope  to have explained .

m.ananth@hotmail.ca