Who is Wilhemina 'Mina' Smiths from Dicey's Song and what is their importance?

Mina is a student at Dicey's school. Mina is one of the most intelligent girls in school like Dicey and she seems drawn to Dicey. Mina later tells Dicey that she likes her because she does not focus on things like boys and having babies. Mina becomes a strong ally to Dicey and defends her when their English teacher decides Dicey has plagiarized a paper she wrote for class. In the end, Mina becomes one of Dicey's first and only friends.