First, the length of the slug needs to be measured as accurately as possible.  A Vernier caliper is used for this type of measurement.  You will need to measure both slugs to complete this part of the experiment.  On this web page only one slug's measurements have been shown.  First clamp the slug securely between the two lower arms.  Then read the length from the Vernier scale using the two step procedure already described.  In this case the index line on the Vernier scale lies between 7.2 cm and 7.3 cm marks on the main scale and the 5th mark on the Vernier scale lines up exactly with the mark on the main scale above it.  This gives a total length of 7.25 cm.
The diameter of the slug is measured in a similar way except, the two lower arms are now clamped snugly around the body of the slug.  The diameter of this slug is measured as 0.95 cm.  The index line on the Vernier scale is in between 0.9 cm and 1.0cm, and the fifth mark on the Vernier scale lines up exactly with a mark on the main scale above.  NOTE:  The mark underneath the number 1 is not actually where  1 cm begins, it is the taller mark to the right of the number 1.

To calculate the volume of each slug the formula V = ()(r)2(h)

Sample calculation is  volume = (3.1416) * (diameter / 2)2 * (height)

                            volume = (3.1416) * (0.95 cm / 2)2 * (7.25 cm)

         volume = 5.14 cm3