Question

1. i think that rock from the mantle is added to the edges of both plates at

plate boundaries.

Explanation:

To solve this fill - in - the - blank question about plate boundaries, we need to recall the types of plate boundaries and their characteristics:

Step 1: Recall plate boundary types

There are three main types of plate boundaries: convergent, divergent, and transform. At divergent plate boundaries, tectonic plates move away from each other.

Step 2: Analyze the process of rock addition

When plates move apart at a divergent boundary (such as mid - ocean ridges), magma from the mantle rises up to fill the gap. This magma then cools and solidifies, adding new rock (oceanic crust) to the edges of the separating plates. At convergent boundaries, one plate is usually subducted (pushed down) into the mantle, and at transform boundaries, plates slide past each other without the addition of new rock from the mantle to the plate edges.

Answer:

divergent