?????????? how big be a brik ?????????
tu get volume av the cylinder with hole in it...leng* base area
base area=pi*(bigrad^2 - small rad^2)
small diam=0.45, so small rad=0.225 meter....square=0.0625
big diam=0.45+2* wall thik= 0.45+0.46=0.91
big rad=0.455 meter...square=0.207025
area=pi*(0.207025-0.0625)=3.14159*0.144525=0.454038677
volume=hite*area=1.5*0.454038677=0.681058016