How do the crystallization and settling of the earliest formed minerals affect the composition of the remaining magma?

The process of crystallization comprises of two main steps:
1. Nucleation
2. Growth

When the early setting minerals have crystallized, they provide a surface for the remaining minerals in the magma to crystallize. They do this by providing a surface for the nucleation to occur. Once nucleation has occurred, the crystals grow in size.

Read the sentences below in 1962, i tried to enroll as the first black student at the university of mississippi. the governor of mississippi blocked my entrance which best describes the verbs used in the sentences? o they are past tense verbs, which are often used in narrative essays o they are past tense verbs, which are not often used in narrative essays. o they are future tense verbs, which are often used in narrative essays o they are future tense verbs, which are not often used in narrative essays.