Question 983991
A hollow cylindrical object has an inner radius of 3cm and an outer radius of 4cm,and a height of 8 cm.It is made of a material whose density is 5gm/cm3.  Write the mass of this object in kilograms. 
---------------
Find the volume.
Vol = volume of a cylinder with r = 4 minus a cylinder with r = 3
--------
Multiply the volume by 5 --> mass in grams.
Divide by 1000