Answer is: the volume of an irregular object is 4,00 ml.
Volume is the amount of space the object occupies and can be finded immersing it in water in a container with volume markings and than see how much the level of the container changes (goes up).
V(irregular object) = V(final volume) - V(initial volume).
V(irregular object) = 7,50 ml - 3,50 ml.
V(irregular object) = 4,00 ml.
