Alisa placed a small seashell on the pan of a balance. What other tool does she need to determine the density of the seashell?

To determine the density of the seashell, Alisa needs a graduated cylinder or another container to measure the volume of water displaced by the seashell. By measuring the mass of the seashell on the balance and calculating the volume of water displaced, she can then use the formula density = mass/volume to find the density of the seashell.