If the shape of an object is irregular, like a stone, how can you measure its volume?

You put water into a graduated cylinder or beaker measure the height of the water then put the rock in and it will displace the water by its volume so you take the new height of water with the rock in and subtract it by the original height.
x=water with rock
y=water without rock
x-y

40 because it’s just a little longer than 32 feet