Question

analyzing the properties of rocks in earths layers
layer | density (g/cm³) - top | density (g/cm³) - bottom
crust | 2.2 | 2.9
upper mantle | 3.4 | 4.4
lower mantle | 4.4 | 5.6
you have learned that different types of rocks are found in earths layers. their composition affects their densities.
what can you conclude based on the information in the table?

• the rocks in the crust are the most dense
• the rocks in the upper mantle are the most dense
• the rocks in the lower mantle are the most dense
• the rocks in the core are the most dense

Explanation:

To determine the most dense rocks, we compare the maximum density values of each layer:

• Crust: max density is 2.9 g/cm³.
• Upper mantle: max density is 4.4 g/cm³.
• Lower mantle: max density is 5.6 g/cm³.
• Core: Not in the table, but among the given layers (Crust, Upper Mantle, Lower Mantle), the Lower Mantle has the highest max density (5.6 g/cm³). Wait, no—wait, the options include "The rocks in the lower mantle are the most dense" and others. Wait, let's re - check:

Crust top: 2.2, bottom: 2.9.
Upper mantle top: 3.4, bottom: 4.4.
Lower mantle top: 4.4, bottom: 5.6.
Now, comparing the bottom (or top, but bottom is deeper) densities: 2.9 (Crust) < 4.4 (Upper Mantle bottom) < 5.6 (Lower Mantle bottom). So the Lower Mantle's rocks (at the bottom) have the highest density among the given layers in the table. Wait, but the options:

1. "The rocks in the crust are the most dense" — no, 2.9 is less than 4.4 and 5.6.
2. "The rocks in the upper mantle are the most dense" — 4.4 is less than 5.6.
3. "The rocks in the lower mantle are the most dense" — 5.6 is higher than 2.9 and 4.4.
4. "The rocks in the core are the most dense" — The table doesn't have core data, but among the provided layers (Crust, Upper Mantle, Lower Mantle), Lower Mantle has the highest density. Wait, but maybe I misread. Wait, the lower mantle's bottom density is 5.6, which is higher than upper mantle's 4.4 and crust's 2.9. So the correct conclusion is that the rocks in the lower mantle are the most dense (from the given data in the table).

Answer:

The rocks in the lower mantle are the most dense. (Corresponding option: The rocks in the lower mantle are the most dense.)