The level in the beaker will increase because the volumes of the spheres will also be added to the volume of the water. First, we must determine the volume of each sphere. For this, we will use:
density = mass / volume We can check the density of both aluminum and iron in literature, and given the mass, we may obtain the volume.
Aluminum: Density = 2.70 g/ml Mass = 20.4 g Volume = 20.4 / 2.7 = 7.56 ml
Iron: Density = 7.87 g/ml Mass = 49.4 g Volume = 49.4 / 7.87 = 6.28 ml
Now, we add these volumes to the volume of water present: 75.2 + 6.28 + 7.56 = 89.04
