a graduated cylinder is used to measure volume of an object & a balance is used for measuring the mass of an object & density can be calculated by measuring the mass of an object divided by the volume of that object ->  the density of an object can be measured using a graduated cylinder and a balance  the density of an object can be measured using a graduated cylinder and a balance & a marble is a kind of object -> the density of a marble can be measured using a graduated cylinder and a balance