compared to the euro-american teacher, the navajo teacher discussed in your text was in response to children's statements.

Compared to the Euro-American teacher, the Navajo teacher discussed in your text was slower in response to children's statements. The answer can be found in page 207 of the book:

"However, teachers often communicate in the style of their own culture. For example, the time a teacher waits for a child to respond to a question and the time the teacher waits before talking again were compared between a Euro-American and a Navajo teacher of the same group of third-grade Navajo students (White & Tharp, 1988). The Navajo teacher waited considerably longer than the Euro-American teacher after the children responded before talking again. "

The one that most represents the earths mantle would be the skin since the mantle is the upper part of the earths depths which is just like the skin of an apple.